Alex Zettl

Alex K. Zettl (born Oct. 11, 1956) is an American experimental physicist, educator, and inventor.

Alex Zettl
Alma mater	B.A. University of California, Berkeley, Ph.D. University of California, Los Angeles
Known for	Nanoscale constructs
Scientific career
Institutions	Lawrence Berkeley National Laboratory, University of California, Berkeley

He is a Professor of the Graduate School in Physics at the University of California, Berkeley, and a Senior Scientist at the Lawrence Berkeley National Laboratory. Zettl is a leading expert in the synthesis, characterization, and application of low dimensional materials. He has synthesized and studied new materials, notably those based on carbon, boron and nitrogen, and has made numerous inventions in the field of electronic materials and nano-electromechanical systems. Zettl and his research team were the first to synthesize boron nitride nanotubes,^{[1][2][circular reference]} and created carbon nanotube chemical sensors.^[3] He and his team built the world's smallest synthetic electrically-powered rotational nanomotor,^[4] the smallest fully integrated FM radio receiver,^[5][6] a nanomechanical mass balance with single-atom sensitivity,^[7] voltage-controllable nanoscale relaxation oscillators,^[8][9] and a nanoscale thermal rectifier^[10] useful for phononic circuitry He and his team invented the nanomanipulator,^[11][12] suspended graphene grid,^[13][14] and the graphene liquid cell^[15] and graphene flow cell,^[16] all of which have greatly advanced transmission electron microscopy.

Early life and education

Zettl was born in San Francisco, California. He attended Sir Francis Drake High School (now Archie Williams High School), the University of California, Berkeley (A.B. 1978) and the University of California, Los Angeles (M.S. 1980, Ph.D. 1983). His doctoral field of study was experimental condensed matter physics. His Ph.D. advisor was Prof. George Grüner.

Career

As a graduate student, Zettl closely collaborated with two-time Physics Nobel Laureate John Bardeen. Bardeen had developed a new theory of macroscopic quantum tunneling of charge density waves, and Zettl performed experiments to test the theory.^[17][18] After completing his Ph.D., Zettl immediately assumed a faculty position in the Physics Department at the University of California, Berkeley, and has remained there throughout his academic career (Assistant Professor, 1983–86; Associate Professor, 1986-1988; Professor, 1988-2022; Professor of the Graduate School in Physics, 2022–present).

At the Lawrence Berkeley National Laboratory Zettl led the superconductivity program from 1990 to 2002, and the sp2-bonded materials program from 1997 to 2022. From 2004 to 2014 he directed the National Science Foundation funded Center of Integrated Nanomechanical Systems. The Center brought together approximately 25 research teams from four institutions (UC Berkeley, Stanford University, California Institute of Technology, and UC Merced) and fostered highly interdisciplinary nanoelectromechanical research. The Center also developed numerous educational outreach programs. From 2013 to 2015 Zettl was co-Director (along with Carolyn Bertozzi), and from 2015 to 2022 Director, of the Berkeley Nanosciences and Nanoengineering Institute (BNNI), an umbrella organization for expanding and coordinating Berkeley research and educational activities in nanoscale science and engineering.

Zettl has advised approximately 50 graduate students (including those earning Ph.D. degrees in chemistry, mechanical engineering, electrical engineering, and materials science), and approximately 40 postdoctoral researchers.

Selected research accomplishments

Access to Zettl's 600+ research publications, supplementary materials, and research highlights can be found at https://www.ocf.berkeley.edu/~jode/index.html.

Charge density wave statics and nonlinear dynamics

Zettl discovered chaotic response^[19] and period doubling routes to chaos^[20] in dynamic charge density wave (CDW) systems driven by an rf field, and found that mode locking completely freezes out all internal fluctuations of the collective mode condensate.^[21][22] He identified phase slip centers as the origin of so-called switching in CDWs.^[23] He discovered unusual electro-elastic coupling in CDW systems, and studied the evolution of the CDW order parameter as sample sizes approached the nm scale.^[24] For the 2D static CDW system TaS₂, Zettl used cryogenic STM measurements to fully characterize domain structure,^[25] and to contrast bulk CDW parameters determined via x-ray scattering to surface CDW parameters established by STM.^[26]

High temperature superconductors and fullerenes

Zettl performed seminal isotope effect measurements in high temperature superconductors, including substituting oxygen,^[27][28] barium,^[29] and copper^[29] isotopes in Y-Ba-Cu-O, substituting oxygen isotopes in La-Sr-Cu-O,^[30] and substituting carbon and alkali isotopes^[31][32] in A₃C₆₀. These measurements placed severe constraints on the superconductivity mechanism, and revealed that superconductivity in the copper oxides was likely not phonon-mediated, but likely was phonon mediated in the fullerenes. Zettl was the first to intercalate high-T_c superconductors with foreign molecules^[33] which allowed Cu-O planes to be physically and electronically separated. Zettl also produced high quality single crystals^[34] of fullerene superconductors which facilitated a host of detailed transport and thermodynamic measurements. Zettl revealed the elastic properties of high-T_c materials,^[35] and determined the effective dimensionality of fullerene superconductors via paraconductivity measurements.^[36]

Carbon and boron nitride nanotubes and related nanostructures

Zettl has performed extensive studies on the mechanical and electronic properties of carbon nanotubes (CNTs). He created electronic devices from CNTs, including a rectifier^[37] and chemical sensor.^[38] From thermal conductivity measurements^[39] he extracted the linear-T behavior expected from the quantum of thermal conductance. He created a highly robust CNT-based electron field emission source.^[39] Zettl discovered that CNTs could be stable in a fully collapsed state,^[40] which led to a refined quantification^[41] of the interlayer interaction energy in graphite; this important parameter had previously been surprisingly ill-defined experimentally.

Zettl was the first to synthesize boron nitride nanotubes (BNNTs),^[1] for which (in sharp contrast to CNTs), the electronic and optical properties are relatively insensitive to wall number, diameter, and chirality. Zettl also found different ways to efficiently synthesize^{[42][43][44][45][46]} BNNTs, along with related BN-based nanomaterials such as BN nanococoons^[46] and BN aerogels.^[47] He also developed methods to functionalize the outer surfaces of BNNTs,^[48][49][50] and fill them with foreign chemical species^[51][52] creating new structures including silocrystals.^[53] Zettl showed experimentally that an electric field could be used to modulate the electronic band gap of BNNTs (giant Stark effect).^[54]

Nanoelectromechanical systems and advances in transmission electron microscopy

Zettl developed the transmission electron microscope (TEM) nanomanipulator,^[11][12] which allowed electrical and mechanical stimulation of nanoscale samples while they were being imaged inside the TEM. The nanomanipulator could be configured as a mechanical and/or electrical probe placed with atomic precision, as a scanning tunneling microscope, or as an atomic force microscope with simultaneous force measurement capability.^[55] Zettl used the nanomanipulator to prove that multi-wall CNT were composed of nested concentric cylinders rather than scrolls,^[12] and he determined the fundamental frictional forces between the cylinders.^[12][55] This led to his invention of the rotational nanomotor^[4] that employed nanotube bearings. Other inventions by Zettl that resulted were surface-tension-powered relaxation oscillators,^[8] tunable resonators,^[56] nanocrystal-powered linear motors,^[57] a fully integrated nanoradio receiver,^[4] a nanoballoon actuator,^[58] and nano-scale electrical^[59] and thermal^[60] rheostats. Zettl used the nanomanipulator to perform the first electron holography experiments^[61] on nanoscale materials, which quantified quantum mechanical field emission from CNTs. Using an architecture similar to that of his nanoradio, Zettl created a nanoelectromechanical “balance” which had single atom mass sensitivity, and with which he observed atomic shot noise for the first time.^[7] He developed a suspended graphene membrane^[13][14] that allowed for nearly real-time TEM imaging of individual carbon atom dynamics, and other isolated atomic and molecular species. Zettl's development of the TEM graphene liquid cell^[15] and graphene flow cell^[16] brought ultra-high-resolution real-time liquid phase imaging to the TEM world. Zettl also developed nanomechanical biological probes,^[62] tailored nanopores,^[63][64][65] and highly efficient wideband graphene-based mechanical energy transducers.^[66][67]

2D materials

Zettl has made key contributions to the synthesis and characterization of a host of 2D materials, including TaS₂,^[25][26] MoS₂,^[68][69] alloyed NbS₂,^[70] NbSe₂,^[71] and 2D quasicrystals.^[72] Zettl recently discovered a means to enhance and control quantum light emission in hexagonal-BN heterostructures,^[73] with implications for quantum information transmission and management.

Isolation of 1D chains and topological materials

In analogy to the isolation of 2D graphene from graphite, Zettl developed a method by which single or few chains of quasi 1D materials could be isolated and studied.^[74][75] He did this by synthesizing the materials in the confined (and protective) interior of CNTs and BNNTs. The method has yielded structures unknown in “bulk”, with often interesting electronic properties (such as sharp metal-to-insulator transitions^[76]) and non-trivial topological properties.^[77] Atomically-precise ultra-narrow nanoribbons^[78] were also created by Zettl via this confined growth method.

Liquid electronics

Using conducting nanoparticles softly “jammed” at the interface between two immiscible liquids, Zettl constructed electronic devices and “circuitry”, thus realizing an effective paradigm for “all liquid electronics”.^[79] Such constructs could facilitate easier reconfiguration or complete recycling of constituents once the circuit architecture becomes obsolete.

Selected books, book chapters, and review articles

• S. Saito and A. Zettl, eds. Carbon Nanotubes: Quantum Cylinders of Graphene.

Contemporary Concepts of Condensed Matter Science, Volume 3, Pages 1–215 (2008)

• G. Grüner and A. Zettl. Charge density wave conduction: a novel collective transport phenomenon in solids. Phys. Reports 119, 117 (1985)
• A. Zettl. Chaos in solid state systems. In Methods and Applications of Nonlinear Dynamics, ACIF Series vol. 7, A. Saenz, ed. (World Scientific, Singapore, 1988), p. 203
• A. Zettl and G. Grüner. Routes to chaos in charge density wave systems. Comments in Cond. Matt. Phys. 12, 265 (1986)
• S. Brown and A. Zettl. Charge density wave current oscillations and interference effects. In Charge Density Waves in Solids, Modern Problems in Condensed Matter Science Series vol. 25, L. Gor'kov and G. Grüner, eds. (Elsevier, Amsterdam, 1989)
• A. Zettl, W.A. Vareka, and X.-D. Xiang. Intercalating high Tc oxide superconductors. In Quantum Theory of Real Materials, J.R. Chelilowsky and S.G. Louie, eds. (Kluwer Academic Publishers, Boston, 1996) p. 425
• J. C. Grossman, C. Piskoti, and A. Zettl. Molecular and Solid C36. In Fullerenes: Chemistry, Physics, and Technology, K. Kadish and R. Ruoff, ed. Chap 20, 887-916 (2000)
• N.G. Chopra and A. Zettl. Boron-Nitride-Containing Nanotubes. In Fullerenes: Chemistry, Physics, and Technology, K. Kadish and R. Ruoff, eds. Chap.17, 767-794 (2000)
• A. Zettl. New carbon materials. McGraw Hill Yearbook of Science & Technology. (McGraw Hill, 1999)
• A. Zettl and J. Cumings. Elastic properties of fullerenes. In Handbook of Elastic Properties of Solids, Liquids, and Gases, Levy, Bass, and Stern, eds. (Academic Press, 2000) Chapt. 11, pp. 163–171
• A. Kis and A. Zettl. Nanomechanics of carbon nanotubes. Phil. Trans. R. Soc. A 366, 1591-1611 (2008)
• M.L. Cohen and A. Zettl. The physics of boron nitride nanotubes. Physics Today 63 (11), 34-38 (2010)
• J. Park, V.P. Adiga, A. Zettl, and A.P. Alivisatos. High resolution imaging in the graphene liquid cell. In Liquid Cell Electron Microscopy, F.M. Ross, ed. (Cambridge University Press, Cambridge, U.K., (2017) p. 393.

Awards and honors

IBM Pre–doctoral Fellowship (1982-1983); Presidential Young Investigator Award (1984–1989); Sloan Foundation Fellowship (1984–1986); IBM Faculty Development Award (1985–1987); Miller Professorship (1995); Lawrence Berkeley National Laboratory Outstanding Performance Award (1995); Lucent Technologies Faculty Award (1996); Fellow of the American Physical Society (1999); Lawrence Berkeley National Laboratory Outstanding Performance Award (2004); R&D 100 Award (2004); APS James C. McGroddy Prize for New Materials (Shared with Hongjie Dai) (2006), Miller Professorship (2007); R&D 100 Award (2010); Feynman Prize in Nanotechnology, Experimental (2013); Membership, American Academy of Arts and Sciences (2014); R&D 100 Award (2015); Clarivate Citation Laureate (2020)

Personal life

Zettl is an outdoor enthusiast. He is an avid sea and whitewater kayaker and a whitewater rafter. He has guided numerous whitewater raft trips on class 5 rivers throughout California, and has guided wilderness descents of the Tatshenshini and Alsek Rivers in Alaska and a mid-winter descent of the Colorado River through the Grand Canyon. Zettl enjoys backcountry skiing and mountaineering, especially expedition climbing. He has led or co-led numerous climbing expeditions to the Alaska Range, the Saint Elias Range (Alaska and the Yukon), and the Andes of Ecuador, Peru, and Argentina. He has climbed technical routes on Denali, and completed a ski descent of Mt. Logan, Canada's highest peak. He has climbed extensively in the Sierra Nevada of California, the Cascades of the Pacific Northwest, the volcanoes of Mexico, the Alps of Germany, France, Switzerland, and Italy, the peaks of Morocco and Tanzania, the Alps of Japan and New Zealand, and in the Himalaya and Karakoram of Nepal and Pakistan. Zettl also enjoys designing and constructing amateur electronics, and building and operating off-road vehicles.

References

1. Chopra, Nasreen G.; Luyken, R. J.; Cherrey, K.; Crespi, Vincent H.; Cohen, Marvin L.; Louie, Steven G.; Zettl, A. (18 August 1995). "Boron Nitride Nanotubes". Science. 269 (5226): 966–967. doi:10.1126/science.269.5226.966. PMID 17807732. S2CID 28988094.
2. "Boron Nitride Nanotubes". Wikipedia.
3. Collins, Philip G.; Bradley, Keith; Ishigami, Masa; Zettl, A. (10 March 2000). "Extreme Oxygen Sensitivity of Electronic Properties of Carbon Nanotubes". Science. 287 (5459): 1801–1804. doi:10.1126/science.287.5459.1801. PMID 10710305.
4. Fennimore, A. M.; Yuzvinsky, T. D.; Han, Wei-Qiang; Fuhrer, M. S.; Cumings, J.; Zettl, A. (July 2003). "Rotational actuators based on carbon nanotubes". Nature. 424 (6947): 408–410. doi:10.1038/nature01823. PMID 12879064. S2CID 2200106.
5. Jensen, K.; Weldon, J.; Garcia, H.; Zettl, A. (1 November 2007). "Nanotube Radio". Nano Letters. 7 (11): 3508–3511. doi:10.1021/nl0721113. PMID 17973438.
6. Regis, Ed (2009). "The World's Smallest Radio". Scientific American. 300 (3): 40–45. doi:10.1038/scientificamerican0309-40. PMID 19253772.
7. Jensen, K.; Kim, Kwanpyo; Zettl, A. (September 2008). "An atomic-resolution nanomechanical mass sensor". Nature Nanotechnology. 3 (9): 533–537. arXiv:0809.2126. doi:10.1038/nnano.2008.200. PMID 18772913. S2CID 11406873.
8. Regan, B. C.; Aloni, S.; Ritchie, R. O.; Dahmen, U.; Zettl, A. (April 2004). "Carbon nanotubes as nanoscale mass conveyors". Nature. 428 (6986): 924–927. doi:10.1038/nature02496. PMID 15118721. S2CID 4430369.
9. Regan, B. C.; Aloni, S.; Jensen, K.; Zettl, A. (21 March 2005). "Surface-tension-driven nanoelectromechanical relaxation oscillator". Applied Physics Letters. 86 (12): 123119. doi:10.1063/1.1887827.
10. Chang, C. W.; Okawa, D.; Majumdar, A.; Zettl, A. (17 November 2006). "Solid-State Thermal Rectifier". Science. 314 (5802): 1121–1124. doi:10.1126/science.1132898. PMID 17110571. S2CID 19495307.
11. Cumings, John; Collins, Philip G.; Zettl, A. (August 2000). "Peeling and sharpening multiwall nanotubes". Nature. 406 (6796): 586. doi:10.1038/35020698. PMID 10949291. S2CID 33223709.
12. Cumings, John; Zettl, A. (28 July 2000). "Low-Friction Nanoscale Linear Bearing Realized from Multiwall Carbon Nanotubes". Science. 289 (5479): 602–604. doi:10.1126/science.289.5479.602. PMID 10915618.
13. Meyer, Jannik C.; Kisielowski, C.; Erni, R.; Rossell, Marta D.; Crommie, M. F.; Zettl, A. (12 November 2008). "Direct Imaging of Lattice Atoms and Topological Defects in Graphene Membranes". Nano Letters. 8 (11): 3582–3586. doi:10.1021/nl801386m. PMID 18563938.
14. Girit, Çağlar Ö.; Meyer, Jannik C.; Erni, Rolf; Rossell, Marta D.; Kisielowski, C.; Yang, Li; Park, Cheol-Hwan; Crommie, M. F.; Cohen, Marvin L.; Louie, Steven G.; Zettl, A. (27 March 2009). "Graphene at the Edge: Stability and Dynamics". Science. 323 (5922): 1705–1708. doi:10.1126/science.1166999. PMID 19325110. S2CID 24762146.
15. Yuk, Jong Min; Park, Jungwon; Ercius, Peter; Kim, Kwanpyo; Hellebusch, Daniel J.; Crommie, Michael F.; Lee, Jeong Yong; Zettl, A.; Alivisatos, A. Paul (6 April 2012). "High-Resolution EM of Colloidal Nanocrystal Growth Using Graphene Liquid Cells". Science. 336 (6077): 61–64. doi:10.1126/science.1217654. PMID 22491849. S2CID 12984064.
16. Dunn, Gabriel; Adiga, Vivekananda P.; Pham, Thang; Bryant, Christopher; Horton-Bailey, Donez J.; Belling, Jason N.; LaFrance, Ben; Jackson, Jonathan A.; Barzegar, Hamid Reza; Yuk, Jong Min; Aloni, Shaul; Crommie, Michael F.; Zettl, Alex (25 August 2020). "Graphene-Sealed Flow Cells for In Situ Transmission Electron Microscopy of Liquid Samples". ACS Nano. 14 (8): 9637–9643. doi:10.1021/acsnano.0c00431. PMID 32806056. S2CID 221164696.
17. Grüner, G.; Zettl, A.; Clark, W.G.; Bardeen, John (15 December 1981). "Field and frequency dependence of charge-density-wave conduction in NbSe₃". Physical Review B. 24 (7247): 7247–7257. doi:10.1103/PhysRevB.24.7247.
18. Bardeen, J.; Ben-Jacob, E.; Zettl, A.; Grüner, G. (16 August 1982). "Current Oscillations and Stability of Charge-Density-Wave Motion in NbSe₃". Physical Review Letters. 49 (493): 493–496. doi:10.1103/PhysRevLett.49.493.
19. Sherwin, M.; Hall, R.; Zettl, A. (1 October 1984). "Chaotic ac Conductivity in the Charge-Density-Wave State of (TaSe₄)₂I". Physical Review Letters. 53 (1387): 1387–1390. doi:10.1103/PhysRevLett.53.1387.
20. Sherwin, M.S.; Zettl, A. (1 October 1984). "Chaotic response of NbSe₃: Evidence for a new charge-density-wave phase". Physical Review Letters. 53 (1387): 1387. doi:10.1103/PhysRevLett.53.1387.
21. Sherwin, M.S.; Zettl, A. (15 October 1985). "Complete charge density-wave mode locking and freeze-out of fluctuations in NbSe₃". Physical Review B. 32 (5536(R)): 5536–5539. doi:10.1103/PhysRevB.32.5536. PMID 9937795.
22. Hall, R.P.; Hundley, M.F.; Zettl, A. (2 June 1986). "Switching and Phase-Slip Centers in Charge-Density-Wave Conductors". Physical Review Letters. 56 (2399): 2399–2402. doi:10.1103/PhysRevLett.56.2399. PMID 10032976.
23. Bourne, L.C.; Sherwin, M.S.; Zettl, A. (5 May 1986). "Elastic Properties of Charge-Density-Wave Conductors: ac-dc Electric Field Coupling". Physical Review Letters. 56 (1952): 1952–1955. doi:10.1103/PhysRevLett.56.1952. PMID 10032819.
24. Onishi, Seita; Jamei, Mehdi; Zettl, Alex (1 February 2017). "Narrowband noise study of sliding charge density waves in NbSe3 nanoribbons". New Journal of Physics. 19 (2): 023001. doi:10.1088/1367-2630/aa5912.
25. Burke, B.; Thomson, R.E.; Zettl, A.; Clarke, John (1991). "Charge-density-wave domains in 1T-TaS₂ observed by satellite structure in scanning-tunneling-microscopy images". Physical Review Letters. 66 (23): 3040–3043. doi:10.1103/PhysRevLett.66.3040. PMID 10043683.
26. Burk, B.; Thomson, R. E.; Clarke, John; Zettl, A. (17 July 1992). "Surface and Bulk Charge Density Wave Structure in 1 T-TaS₂". Science. 257 (5068): 362–364. doi:10.1126/science.257.5068.362. PMID 17832831. S2CID 8530734.
27. Bourne, L. C.; Crommie, M. F.; Zettl, A.; Loye, Hans-Conrad zur; Keller, S. W.; Leary, K. L.; Stacy, Angelica M.; Chang, K. J.; Cohen, Marvin L.; Morris, Donald E. (1 June 1987). "Search for Isotope Effect in Superconducting Y-Ba-Cu-O". Physical Review Letters. 58 (22): 2337–2339. doi:10.1103/PhysRevLett.58.2337. PMID 10034719.
28. Hoen, S.; Creager, W. N.; Bourne, L. C.; Crommie, M. F.; Barbee, T. W.; Cohen, Marvin L.; Zettl, A.; Bernardez, Luis; Kinney, John (1 February 1989). "Oxygen isotope study of YBa₂Cu₃O₇". Physical Review B. 39 (4): 2269–2278. doi:10.1103/physrevb.39.2269. PMID 9948464.
29. Bourne, L. C.; Zettl, A.; Barbee, T. W.; Cohen, Marvin L. (1 September 1987). "Complete absence of isotope effect in Y Ba 2 Cu 3 O 7 : Consequences for phonon-mediated superconductivity". Physical Review B. 36 (7): 3990–3993. doi:10.1103/physrevb.36.3990. PMID 9943360.
30. Faltens, Tanya A.; Ham, William K.; Keller, Steven W.; Leary, Kevin J.; Michaels, James N.; Stacy, Angelica M.; zur Loye, Hans-Conrad; Morris, Donald E.; Barbee III, T. W.; Bourne, L. C.; Cohen, Marvin L.; Hoen, S.; Zettl, A. (24 August 1987). "Observation of an oxygen isotope shift in the superconducting transition temperature of La_1.85Sr_0.15CuO₄". Physical Review Letters. 59 (8): 915–918. doi:10.1103/PhysRevLett.59.915. PMID 10035905.
31. Fuhrer, M.S.; Cherrey, K.; Zettl, A. (August 1997). "Carbon isotope effect in single-crystal Rb₃C₆₀". Physica C: Superconductivity. 282–287: 1917–1918. doi:10.1016/S0921-4534(97)01010-1.
32. Burk, B.; Crespi, Vincent H.; Zettl, A.; Cohen, Marvin L. (6 June 1994). "Rubidium isotope effect in superconducting Rb₃C₆₀". Physical Review Letters. 72 (23): 3706–3709. doi:10.1103/PhysRevLett.72.3706. PMID 10056269.
33. Xiang, X-D.; McKernan, S.; Vareka, W. A.; Zettl, A.; Corkill, J. L.; Barbee, T. W.; Cohen, Marvin L. (November 1990). "Iodine intercalation of a high-temperature superconducting oxide". Nature. 348 (6297): 145–147. doi:10.1038/348145a0. S2CID 4369061.
34. Xiang, X. -D.; Hou, J. G.; Briceño, G.; Vareka, W. A.; Mostovoy, R.; Zettl, A.; Crespi, Vincent H.; Cohen, Marvin L. (22 May 1992). "Synthesis and Electronic Transport of Single Crystal K₃C₆₀". Science. 256 (5060): 1190–1191. doi:10.1126/science.256.5060.1190. PMID 17795215. S2CID 11537235.
35. Hoen, S.; Bourne, L. C.; Kim, Choon M.; Zettl, A. (1 December 1988). "Elastic response of polycrystalline and single-crystal Y Ba₂Cu₃O₇". Physical Review B. 38 (16): 11949–11951. doi:10.1103/physrevb.38.11949. PMID 9946111.
36. Xiang, X.-D.; Hou, J. G.; Crespi, Vincent H.; Zettl, A.; Cohen, Marvin L. (January 1993). "Three-dimensional fluctuation conductivity in superconducting single crystal K₃C₆₀ and Rb₃C₆₀". Nature. 361 (6407): 54–56. doi:10.1038/361054a0. S2CID 4342464.
37. Collins, Philip G.; Zettl, A.; Bando, Hiroshi; Thess, Andreas; Smalley, R. E. (3 October 1997). "Nanotube Nanodevice". Science. 278 (5335): 100–102. doi:10.1126/science.278.5335.100.
38. Sahoo, Satyaprakash; Chitturi, Venkateswara Rao; Agarwal, Radhe; Jiang, Jin-Wu; Katiyar, Ram S. (26 November 2014). "Thermal Conductivity of Freestanding Single Wall Carbon Nanotube Sheet by Raman Spectroscopy". ACS Applied Materials & Interfaces. 6 (22): 19958–19965. doi:10.1021/am505484z. PMID 25350877.
39. Collins, Philip G.; Zettl, A. (23 September 1996). "A simple and robust electron beam source from carbon nanotubes". Applied Physics Letters. 69 (13): 1969–1971. doi:10.1063/1.117638.
40. Chopra, Nasreen G.; Benedict, Lorin X.; Crespi, Vincent H.; Cohen, Marvin L.; Louie, Steven G.; Zettl, A. (September 1995). "Fully collapsed carbon nanotubes". Nature. 377 (6545): 135–138. doi:10.1038/377135a0. S2CID 4351651.
41. Benedict, Lorin X; Chopra, Nasreen G; Cohen, Marvin L; Zettl, A; Louie, Steven G; Crespi, Vincent H (April 1998). "Microscopic determination of the interlayer binding energy in graphite". Chemical Physics Letters. 286 (5–6): 490–496. doi:10.1016/S0009-2614(97)01466-8.
42. Han, Wei-Qiang; Cumings, John; Zettl, Alex (30 April 2001). "Pyrolytically grown arrays of highly aligned B_xC_yN_z nanotubes". Applied Physics Letters. 78 (18): 2769–2771. doi:10.1063/1.1369620.
43. Cumings, John; Zettl, A. (January 2000). "Mass-production of boron nitride double-wall nanotubes and nanococoons". Chemical Physics Letters. 316 (3–4): 211–216. doi:10.1016/S0009-2614(99)01277-4.
44. Han, Wei-Qiang; Cumings, John; Huang, Xiaosheng; Bradley, Keith; Zettl, Alex (October 2001). "Synthesis of aligned B_xC_yN_z nanotubes by a substitution-reaction route". Chemical Physics Letters. 346 (5–6): 368–372. doi:10.1016/S0009-2614(01)00993-9.
45. Han, Wei-Qiang; Mickelson, W.; Cumings, John; Zettl, A. (5 August 2002). "Transformation of B_xC_yN_z nanotubes to pure BN nanotubes". Applied Physics Letters. 81 (6): 1110–1112. doi:10.1063/1.1498494.
46. Fathalizadeh, Aidin; Pham, Thang; Mickelson, William; Zettl, Alex (13 August 2014). "Scaled Synthesis of Boron Nitride Nanotubes, Nanoribbons, and Nanococoons Using Direct Feedstock Injection into an Extended-Pressure, Inductively-Coupled Thermal Plasma". Nano Letters. 14 (8): 4881–4886. doi:10.1021/nl5022915. PMID 25003307.
47. Rousseas, Michael; Goldstein, Anna P.; Mickelson, William; Worsley, Marcus A.; Woo, Leta; Zettl, Alex (22 October 2013). "Synthesis of Highly Crystalline sp²-Bonded Boron Nitride Aerogels". ACS Nano. 7 (10): 8540–8546. doi:10.1021/nn402452p. PMID 24011289.
48. Han, Wei-Qiang; Zettl, Alex (1 February 2003). "Functionalized Boron Nitride Nanotubes with a Stannic Oxide Coating: A Novel Chemical Route to Full Coverage". Journal of the American Chemical Society. 125 (8): 2062–2063. doi:10.1021/ja0292501. PMID 12590530.
49. Ikuno, T.; Sainsbury, T.; Okawa, D.; Fréchet, J.M.J.; Zettl, A. (June 2007). "Amine-functionalized boron nitride nanotubes". Solid State Communications. 142 (11): 643–646. doi:10.1016/j.ssc.2007.04.010.
50. Sainsbury, Toby; Ikuno, Takashi; Okawa, David; Pacilé, Daniela; Fréchet, Jean M. J.; Zettl, Alex (1 September 2007). "Self-Assembly of Gold Nanoparticles at the Surface of Amine- and Thiol-Functionalized Boron Nitride Nanotubes". The Journal of Physical Chemistry C. 111 (35): 12992–12999. doi:10.1021/jp072958n.
51. Han, Wei-Qiang; Zettl, A. (5 April 2004). "Nanocrystal cleaving". Applied Physics Letters. 84 (14): 2644–2645. doi:10.1063/1.1695635.
52. Pham, Thang; Fathalizadeh, Aidin; Shevitski, Brian; Turner, Sally; Aloni, Shaul; Zettl, Alex (13 January 2016). "A Universal Wet-Chemistry Route to Metal Filling of Boron Nitride Nanotubes". Nano Letters. 16 (1): 320–325. doi:10.1021/acs.nanolett.5b03874. PMID 26707874.
53. Mickelson, W.; Aloni, S.; Han, Wei-Qiang; Cumings, John; Zettl, A. (18 April 2003). "Packing C₆₀ in Boron Nitride Nanotubes". Science. 300 (5618): 467–469. doi:10.1126/science.1082346. PMID 12702871. S2CID 206507202.
54. Ishigami, Masa; Sau, Jay Deep; Aloni, Shaul; Cohen, Marvin L.; Zettl, A. (10 February 2005). "Observation of the Giant Stark Effect in Boron-Nitride Nanotubes". Physical Review Letters. 94 (5): 056804. doi:10.1103/PhysRevLett.94.056804. PMID 15783676.
55. Kis, A.; Jensen, K.; Aloni, S.; Mickelson, W.; Zettl, A. (11 July 2006). "Interlayer Forces and Ultralow Sliding Friction in Multiwalled Carbon Nanotubes". Physical Review Letters. 97 (2): 025501. doi:10.1103/PhysRevLett.97.025501. PMID 16907454.
56. Jensen, K.; Girit, Ç.; Mickelson, W.; Zettl, A. (31 May 2006). "Tunable Nanoresonators Constructed from Telescoping Nanotubes". Physical Review Letters. 96 (21): 215503. doi:10.1103/PhysRevLett.96.215503. PMID 16803247.
57. Regan, B. C.; Aloni, S.; Jensen, K.; Ritchie, R. O.; Zettl, A. (1 September 2005). "Nanocrystal-Powered Nanomotor". Nano Letters. 5 (9): 1730–1733. doi:10.1021/nl0510659. PMID 16159214.
58. Barzegar, Hamid Reza; Yan, Aiming; Coh, Sinisa; Gracia-Espino, Eduardo; Dunn, Gabriel; Wågberg, Thomas; Louie, Steven G.; Cohen, Marvin L.; Zettl, Alex (9 November 2016). "Electrostatically Driven Nanoballoon Actuator". Nano Letters. 16 (11): 6787–6791. doi:10.1021/acs.nanolett.6b02394. PMID 27704855.
59. Cumings, John; Zettl, Alex (2002). "Resistance of Telescoping Nanotubes". AIP Conference Proceedings. 633: 227–230. doi:10.1063/1.1514111.
60. Chang, C. W.; Okawa, D.; Garcia, H.; Yuzvinsky, T. D.; Majumdar, A.; Zettl, A. (7 May 2007). "Tunable thermal links". Applied Physics Letters. 90 (19): 193114. doi:10.1063/1.2738187.
61. Cumings, John; Zettl, A.; McCartney, M. R.; Spence, J. C. H. (18 January 2002). "Electron Holography of Field-Emitting Carbon Nanotubes". Physical Review Letters. 88 (5): 056804. doi:10.1103/PhysRevLett.88.056804. PMID 11863765.
62. Chen, Xing; Kis, Andras; Zettl, A.; Bertozzi, Carolyn R. (15 May 2007). "A cell nanoinjector based on carbon nanotubes". Proceedings of the National Academy of Sciences. 104 (20): 8218–8222. doi:10.1073/pnas.0700567104. PMC 1895932. PMID 17485677.
63. Pham, Thang; Gibb, Ashley L.; Li, Zhenglu; Gilbert, S. Matt; Song, Chengyu; Louie, Steven G.; Zettl, Alex (9 November 2016). "Formation and Dynamics of Electron-Irradiation-Induced Defects in Hexagonal Boron Nitride at Elevated Temperatures". Nano Letters. 16 (11): 7142–7147. doi:10.1021/acs.nanolett.6b03442. PMID 27685639.
64. Gilbert, S. Matt; Dunn, Gabriel; Azizi, Amin; Pham, Thang; Shevitski, Brian; Dimitrov, Edgar; Liu, Stanley; Aloni, Shaul; Zettl, Alex (8 November 2017). "Fabrication of Subnanometer-Precision Nanopores in Hexagonal Boron Nitride". Scientific Reports. 7 (1): 15096. doi:10.1038/s41598-017-12684-x. PMC 5678191. PMID 29118413.
65. Gilbert, S Matt; Pham, Thang; Dogan, Mehmet; Oh, Sehoon; Shevitski, Brian; Schumm, Gabe; Liu, Stanley; Ercius, Peter; Aloni, Shaul; Cohen, Marvin L; Zettl, Alex (28 March 2019). "Alternative stacking sequences in hexagonal boron nitride". 2D Materials. 6 (2): 021006. arXiv:1810.04814. doi:10.1088/2053-1583/ab0e24. S2CID 119216315.
66. Zhou, Qin; Zettl, A. (3 June 2013). "Electrostatic graphene loudspeaker". Applied Physics Letters. 102 (22): 223109. arXiv:1303.2391. doi:10.1063/1.4806974. S2CID 29754669.
67. Zhou, Qin; Zheng, Jinglin; Onishi, Seita; Crommie, M. F.; Zettl, Alex K. (21 July 2015). "Graphene electrostatic microphone and ultrasonic radio". Proceedings of the National Academy of Sciences. 112 (29): 8942–8946. doi:10.1073/pnas.1505800112. PMC 4517232. PMID 26150483.
68. Yan, Aiming; Velasco, Jairo; Kahn, Salman; Watanabe, Kenji; Taniguchi, Takashi; Wang, Feng; Crommie, Michael F.; Zettl, Alex (14 October 2015). "Direct Growth of Single- and Few-Layer MoS 2 on h-BN with Preferred Relative Rotation Angles". Nano Letters. 15 (10): 6324–6331. arXiv:1504.06641. doi:10.1021/acs.nanolett.5b01311. PMID 26317240. S2CID 24396802.
69. Yan, Aiming; Chen, Wei; Ophus, Colin; Ciston, Jim; Lin, Yuyuan; Persson, Kristin; Zettl, Alex (25 January 2016). "Identifying different stacking sequences in few-layer CVD-grown Mo S 2 by low-energy atomic-resolution scanning transmission electron microscopy". Physical Review B. 93 (4): 041420. doi:10.1103/PhysRevB.93.041420.
70. Azizi, Amin; Dogan, Mehmet; Cain, Jeffrey D.; Lee, Kyunghoon; Yu, Xuanze; Shi, Wu; Glazer, Emily C.; Cohen, Marvin L.; Zettl, Alex (23 November 2021). "Experimental and Theoretical Study of Possible Collective Electronic States in Exfoliable Re-Doped NbS 2". ACS Nano. 15 (11): 18297–18304. doi:10.1021/acsnano.1c07526. PMID 34739204. S2CID 243801788.
71. Onishi, Seita; Ugeda, Miguel M.; Zhang, Yi; Chen, Yi; Ojeda‐Aristizabal, Claudia; Ryu, Hyejin; Mo, Sung‐Kwan; Hussain, Zahid; Shen, Zhi‐Xun; Crommie, Michael F.; Zettl, Alex (December 2016). "Selenium capped monolayer NbSe 2 for two‐dimensional superconductivity studies". Physica Status Solidi B. 253 (12): 2396–2399. doi:10.1002/pssb.201600235.
72. Cain, Jeffrey D.; Azizi, Amin; Conrad, Matthias; Griffin, Sinéad M.; Zettl, Alex (20 October 2020). "Layer-dependent topological phase in a two-dimensional quasicrystal and approximant". Proceedings of the National Academy of Sciences. 117 (42): 26135–26140. doi:10.1073/pnas.2015164117. PMC 7584993. PMID 33020263.
73. Su, Cong; Zhang, Fang; Kahn, Salman; Shevitski, Brian; Jiang, Jingwei; Dai, Chunhui; Ungar, Alex; Park, Ji-Hoon; Watanabe, Kenji; Taniguchi, Takashi; Kong, Jing; Tang, Zikang; Zhang, Wenqing; Wang, Feng; Crommie, Michael; Louie, Steven G.; Aloni, Shaul; Zettl, Alex (August 2022). "Tuning colour centres at a twisted hexagonal boron nitride interface". Nature Materials. 21 (8): 896–902. doi:10.1038/s41563-022-01303-4. OSTI 1906698. PMID 35835818. S2CID 250535073.
74. Pham, Thang; Oh, Sehoon; Stetz, Patrick; Onishi, Seita; Kisielowski, Christian; Cohen, Marvin L.; Zettl, Alex (20 July 2018). "Torsional instability in the single-chain limit of a transition metal trichalcogenide". Science. 361 (6399): 263–266. arXiv:1803.02866. doi:10.1126/science.aat4749. PMID 30026223. S2CID 49896559.
75. Stonemeyer, Scott; Cain, Jeffrey D.; Oh, Sehoon; Azizi, Amin; Elasha, Malik; Thiel, Markus; Song, Chengyu; Ercius, Peter; Cohen, Marvin L.; Zettl, Alex (31 March 2021). "Stabilization of NbTe3 , VTe3 , and TiTe3 via Nanotube Encapsulation". Journal of the American Chemical Society. 143 (12): 4563–4568. arXiv:2009.10869. doi:10.1021/jacs.0c10175. PMID 33258601. S2CID 221856719.
76. Meyer, Scott; Pham, Thang; Oh, Sehoon; Ercius, Peter; Kisielowski, Christian; Cohen, Marvin L.; Zettl, Alex (9 July 2019). "Metal-insulator transition in quasi-one-dimensional HfTe 3 in the few-chain limit". Physical Review B. 100 (4): 041403. arXiv:1903.00464. doi:10.1103/PhysRevB.100.041403. S2CID 118830779.
77. Pham, Thang; Oh, Sehoon; Stonemeyer, Scott; Shevitski, Brian; Cain, Jeffrey D.; Song, Chengyu; Ercius, Peter; Cohen, Marvin L.; Zettl, Alex (20 May 2020). "Emergence of Topologically Nontrivial Spin-Polarized States in a Segmented Linear Chain". Physical Review Letters. 124 (20): 206403. arXiv:2001.06565. doi:10.1103/PhysRevLett.124.206403. PMID 32501077. S2CID 210839580.
78. Cain, Jeffrey D.; Oh, Sehoon; Azizi, Amin; Stonemeyer, Scott; Dogan, Mehmet; Thiel, Markus; Ercius, Peter; Cohen, Marvin L.; Zettl, Alex (14 April 2021). "Ultranarrow TaS 2 Nanoribbons". Nano Letters. 21 (7): 3211–3217. arXiv:2012.05399. doi:10.1021/acs.nanolett.1c00481. PMID 33818102. S2CID 233029041.
79. Popple, Derek; Shekhirev, Mikhail; Dai, Chunhui; Kim, Paul; Wang, Katherine Xiaoxin; Ashby, Paul; Helms, Brett A.; Gogotsi, Yury; Russell, Thomas P.; Zettl, Alex (27 October 2022). "All‐Liquid Reconfigurable Electronics Using Jammed MXene Interfaces". Advanced Materials. 35 (13): 2208148. doi:10.1002/adma.202208148. PMID 36302090.

External links

• Zettl Group website
• Nanotechnology lecture
• First movie of moving atoms
• BNNI website