Associate Professor Timothy Benseman

Faculty

Timothy Benseman, Associate Professor

TERAHERTZ LASERS & SIGNAL PROCESSING

itomht.yebsnmenaq@.cucyne.ud
(718) 997-3369, SB B208

- Ph.D in Physics, University of Cambridge, United Kingdom, 2007.
- BScHons, MSc in Physics, Victoria University of Wellington, New Zealand, 2002, 2003.

PHYS 222 - Optics
PHYS 637 - Modern Optics

Stacks of intrinsic Josephson junctions (IJJs) in extremely anisotropic high-temperature superconductors such as Bi₂Sr₂CaCu₂O₈ are a promising compact solid-state source of coherent radiation in the 'terahertz gap' range. At present, no such sources exist in the range from approximately 0.5 THz to 1.3 terahertz, and this region is of particular interest for many applications in science, medicine, and high-bandwidth communications, as well as in security and defense. In order to generate technologically useful levels of power from these stacks, it is necessary to obtain efficient phase-synchronized emission from the largest possible number of individual Josephson junctions. Following this approach, I have recently increased the coherent power output from this type of device to 0.6 milliwatts at 0.51 THz, which is approximately the power level required for practical real-time imaging applications.

High temperature superconductors which contain stacked IJJs - namely the bismuth- and thallium-based cuprate compounds - offer a further unique property: they are expected to allow the propagation of Josephson Plasma Waves. Theorists predict that the copper-oxide planes of these HTS cuprates act as natural superconducting waveguides which can channel energy through the structures of these crystals at microwave and terahertz frequencies. My experiments in Bi₂Sr₂CaCu₂O₈ provide strong indirect evidence of this phenomenon. The efficient propagation and non-linearity of Josephson Plasma Waves offers the possibility of novel devices for THz frequency signal processing, such as ridge waveguides, mixers, and modulators/demodulators. Such devices would be extremely valuable for ultra-high bandwidth telecommunications for both wired and wireless applications.

Realizing the full technological potential of complex oxide materials such as these will require advances in thin film growth technology beyond what is presently available, and I am currently developing techniques for growth of thin films with the quality of a single crystal.

Prizes and Awards:

National Science Foundation CAREER Award, 2021. (NSF Engineering Directorate, Division of Electrical, Communications, and Cyber Systems (ECCS).)

Journal Articles:

Stacked Intrinsic Josephson Junction Bi₂Sr₂CaCu₂O₈ Terahertz Sources:
Design Issues for Achieving High Power Output Close to T_c
T. M. Benseman, K. J. Kihlstrom, A. E. Koshelev, U. Welp, W.-K. Kwok, & K. Kadowaki,
Proceedings of the 20^th International Conference on UK-China Emerging Technologies (UCET), Glasgow, UK, September 2020.
IEEE Xplore, doi: 10.1109/UCET51115.2020.9205486.

Observation of a two-mode resonant state in a Bi₂Sr₂CaCu₂O_8+δ mesa device for terahertz emission

T. M. Benseman, A. E. Koshelev, V. Vlasko-Vlasov, Y. Hao, U. Welp, W.-K. Kwok, B. Gross, M. Lange, D. Koelle, R. Kleiner, H. Minami, M. Tsujimoto, & K. Kadowaki,
Physical Review B 100, 144503 (2019).

Temperature and field dependence of the intrinsic tunnelling structure in overdoped Bi₂Sr₂CaCu₂O_8+δ
T. M. Benseman, J. R. Cooper, & G. Balakrishnan,
Physical Review B 98, 014507 (2018).

Thick Bi₂Sr₂CaCu₂O_8+δ films grown by liquid-phase epitaxy for Josephson THz applications
Y. Simsek, V. Vlasko-Vlasov, A. E. Koshelev, T. Benseman, Y. Hao, I. Kesgin, H. Claus, J. Pearson, U. Welp, & W.-K. Kwok,
Superconductor Science & Technology 31, 015009 (2018).

Guiding thermomagnetic avalanches with soft magnetic stripes
V. K. Vlasko-Vlasov, F. Colauto, T. Benseman, D. Rosenmann, & W.-K. Kwok,
Physical Review B 96, 214510 (2017).

Manipulating Abrikosov vortices with soft magnetic stripes
V. K. Vlasko-Vlasov, F. Colauto, A. I. Buzdin, D. Rosenmann, T. Benseman, & W.-K. Kwok,
Physical Review B 95, 174514 (2017).

Magnetic gates and guides for superconducting vortices
V. K. Vlasko-Vlasov, F. Colauto, A. I. Buzdin, D. Rosenmann, T. Benseman, & W.-K. Kwok,
Physical Review B 95, 144504 (2017).

High-resolution thermal micro-imaging using Europium chelate luminescent coatings
T. M. Benseman, Y. Hao, V. Vlasko-Vlasov, U. Welp, A. E. Koshelev, W.-K. Kwok, R. Divan, C. Keiser, C. Watanabe, & K. Kadowaki,
Journal of Visualized Experiments 122, e53948 (2017).

Triode for Magnetic Flux Quanta
V. K. Vlasko-Vlasov, F. Colauto, T. Benseman, D. Rosenmann, & W.-K. Kwok,
Nature Scientific Reports 6, 36847 (2016).

Current filamentation in large Bi₂Sr₂CaCu₂O₈ mesa devices
observed via luminescent and scanning laser thermal microscopy
T. M. Benseman, A. E. Koshelev, V. Vlasko-Vlasov, Y. Hao, W.-K. Kwok, U. Welp, C. Keiser, B. Gross, M. Lange, D. Kölle, R. Kleiner, H. Minami, C. Watanabe, & K. Kadowaki,
Physical Review Applied 3, 044017 (2015).

Antiferromagnetic and nematic phase transitions in BaFe₂(As_1-xP_x)₂
studied by AC micro-calorimetry and SQUID magnetometry
X. Luo, V. Stanev, B. Shen, L. Fang, X. S. Ling, R. Osborn, S. Rosenkranz, T. M. Benseman, R. N. S. Divan, W.-K. Kwok, & U. Welp,
Physical Review B 91, 094512 (2015).

Powerful terahertz emission from Bi₂Sr₂CaCu₂O₈ mesa arrays
T. M. Benseman, K. E. Gray, A. E. Koshelev, W.-K. Kwok, U. Welp, H. Minami, K. Kadowaki, & T. Yamamoto,
Applied Physics Letters 103, 022602 (2013).

The ac Josephson relation and inhomogeneous temperature distributions
in large Bi₂Sr₂CaCu₂O₈ mesas for THz emission
T. M. Benseman, A. E. Koshelev, W.-K. Kwok, U. Welp, K. Kadowaki, J. R. Cooper, & G. Balakrishnan,
Superconductor Science and Technology 26, 085016 (2013).

Jamming of superconducting vortices in a funnel structure
V. Vlasko-Vlasov, T. M. Benseman, U. Welp, & W.-K. Kwok,
Superconductor Science and Technology 26, 075023 (2013).

Direct imaging of hot spot in Bi₂Sr₂CaCu₂O₈ mesa terahertz sources
T. M. Benseman, K. E. Gray, A. E. Koshelev, W.-K. Kwok, U. Welp, V. Vlasko-Vlasov, & K. Kadowaki,
Journal of Applied Physics 113, 133902 (2013).

Tunable terahertz emission from Bi₂Sr₂CaCu₂O₈ mesa devices
T. M. Benseman, A. E. Koshelev, K. E. Gray, W.-K. Kwok, U. Welp, K. Kadowaki, M. Tachiki, & T. Yamamoto,
Physical Review B 84, 064523 (2011).

Valency and spin states of substituent cations in Bi₂Sr₂CaCu₂O₈
T. M. Benseman, J. R. Cooper, C. L. Zentile, L. Lemberger, & G. Balakrishnan,
Physical Review B 84, 144503 (2011).

Evidence for Dirac nodes from quantum oscillations in SrFe₂As₂
M. Sutherland, D. J. Hills, B. S. Tan, M. M. Altarawneh, N. Harrison, J. Gillett, E. C. T. O’Farrell, T. M. Benseman, I. Kokanovic, P. Syers, J. R. Cooper, & S. E. Sebastian,
Physical Review B (Rapid Comm.) 84, 180506(R) (2011).

A detailed de Haas–van Alphen effect study of the overdoped cuprate Tl₂Ba₂CuO₆
P. M. C. Rourke, A. F. Bangura, T. M. Benseman, M. Matusiak, J. R. Cooper, A. Carrington, & N. E. Hussey,
New Journal of Physics 12, 105009 (2010).

Fermi surface and electronic homogeneity of the overdoped cuprate superconductor Tl₂Ba₂CuO₆
as revealed by quantum oscillations
A. F. Bangura, P. M. C. Rourke, T. M. Benseman, M. Matusiak, J. R. Cooper, N. E. Hussey, & A. Carrington,
Physical Review B (Rapid Comm.) 82, 140501(R) (2010).

Increased Tc in Electrolyte-Gated Cuprates
A. S. Dhoot, S. C. Wimbush, T. M. Benseman, J. L. MacManus-Driscoll, J. R. Cooper, & R. H. Friend,
Advanced Materials 22, 2529–2533 (2010).

In-plane oxygen diffusion in single crystals of Bi₂Sr₂CaCu₂O₈
T. M. Benseman, J. R. Cooper, & G. Balakrishnan,
Physica C 468, 81-87 (2008).

The phase diagram of high-Tc superconductors
J. L. Tallon, T. M. Benseman, G. V. M. Williams, & J. W. Loram,
Physica C 415, 9-14 (2004).

Invited Conference Presentations:

Intrinsic Josephson junction Bi₂Sr₂CaCu₂O₈ terahertz sources:
Considerations for enhanced power output and operating temperature
K. J. Kihlstrom, K. C. Reddy, A. E. Koshelev, U. Welp, W.-K. Kwok, K. Kadowaki, & T. M. Benseman,
Presented at the 12th International Conference on Intrinsic Josephson Effect and Horizons of Superconducting Spintronics, Chisinau, Moldova, September 2021.

Intrinsic Josephson junction Bi₂Sr₂CaCu₂O₈ terahertz sources:
Achieving high power output above 77 K
T. M. Benseman, K. J. Kihlstrom, K. C. Reddy, A. E. Koshelev, U. Welp, W.-K. Kwok, & K. Kadowaki,
Presented at the 2021 Vortex Workshop, IISER, India, June 2021.

THz emission at 80 Kelvin from stacked Bi₂Sr₂CaCu₂O₈ Josephson junctions
T. M. Benseman, U. Welp, A. E. Koshelev, V. Vlasko-Vlasov, W.-K. Kwok, & K. Kadowaki,
Presented at PLASMA 2019 Conference, Orlando, Florida, January 2019.

Bi₂Sr₂CaCu₂O₈ Interlayer Josephson Junctions as a coherent Terahertz source:
Recent developments and future outlook
T. M. Benseman, A. E. Koshelev, V. Vlasko-Vlasov, Y. Hao, W.-K. Kwok, U. Welp, B. Gross, M. Lange, D. Kölle, R. Kleiner, H. Minami, C. Watanabe, & K. Kadowaki,
Presented at MORIS 2018 Magnetism & Optics conference, CUNY Queens College, January 2018.

Terahertz radiation from Bi₂Sr₂CaCu₂O₈ interlayer Josephson junctions:
Progress and future strategies
T. M. Benseman, A. E. Koshelev, V. Vlasko-Vlasov, Y. Hao, U. Welp, W.-K. Kwok, B. Gross, M. Lange, D. Koelle, R. Kleiner, & K. Kadowaki,
Presented at 14th International Workshop on High-Frequency Superconducting Electronics, Bjorkliden, Sweden, April 2016.

Terahertz radiation from Bi₂Sr₂CaCu₂O₈ interlayer Josephson junctions:
Progress and future applications
T. M. Benseman, A. E. Koshelev, V. Vlasko-Vlasov, Y. Hao, U. Welp, W.-K. Kwok, B. Gross, M. Lange, D. Koelle, R. Kleiner, & K. Kadowaki,
Presented at Vortex workshop 2015, El Escorial, Spain, May 2015.

Terahertz radiation from Bi₂Sr₂CaCu₂O₈ interlayer Josephson junctions:
Progress and future strategies
T. M. Benseman, A. E. Koshelev, V. Vlasko-Vlasov, Y. Hao, U. Welp, W.-K. Kwok, B. Gross, M. Lange, D. Koelle, R. Kleiner, & K. Kadowaki,
Presented at AMN-7 conference (Advanced Materials & Nanotechnology), Nelson, New Zealand, February 2015.

Powerful coherent terahertz emission from Bi₂Sr₂CaCu₂O₈ mesa array
T. M. Benseman, U. Welp, A. E. Koshelev, K. E. Gray, W.-K. Kwok, H. Minami, K. Kadowaki, & T. Yamamoto,
Presented at PLASMA 2012 Conference, Izmir, Turkey, June 2012.