Terahertz superconducting and semiconducting electronics

Practically all parts of the electromagnetic spectrum are used by humankind. However there is a range of frequencies which is still not employed.  This is so-called terahertz (THz) range and the associated problem is called the terahertz gap. The recent growing interest in terahertz science and technology is due to its many important applications in physics, astronomy, chemistry, biology, and medicine, including THz imaging, spectroscopy, tomography, medical diagnosis, health monitoring, environmental control, as well as chemical and biological identification. This range of the electromagnetic spectrum is situated between 0.3 and 30 THz (Fig 1), which corresponds to 10–1000 mm (wavelength), 1.25–125 meV (energy) or 14–1400 K (temperature). The THz gap, which is still hardly reachable by either electronic or optical devices, covers temperatures of biological processes and a substantial fraction of the luminosity from the Big Bang.

Terahertz radiation (T-rays) may penetrate human bodies but, in contrast with X-rays, cause no damage. The absorption spectrum of T-rays is frequency- and material-dependent. In a frequency range of a few THz the penetration depth through aqueous solutions is very limited, while plastic materials are practically transparent. If tuneable and powerful sources and receivers of such radiation are produced everything can be scanned continuously. This would then initiate a new stage in medicine and in security (Figs 2, 3). Nanostructure-based THz electronics may have many applications, e.g. in ultra-high bandwidth wireless communication networks, vehicle control, atmospheric pollution monitoring, inter-satellite communication and spectroscopy, to name a few. 

Fig 1. Usage of electromagnetic spectrum. The terahertz gap is situated between 0.3 and 30 THz.
Fig 2. Terahertz narcotic detection, THz image (upper) and photograph (lower) of specimens under inspection. Three kinds of powder are hidden in the envelope and can be distinguished using THz time-domain spectroscopy. See A Dobroiu et al, Proc IEEE 95, 1566 (2007). Figure reproduced by kind permission of C Otani (RIKEN).	Fig 3. A liver cancer (a,b) sample was scanned. The cancer areas (indicated by arrows) are seen as brighter. The breast cancer in (c) (indicated by the dotted line) has texture different from the rest. See S Nakajima et al, Appl Phys Lett 90, 041102 (2007). Figure reproduced by kind permission of C Otani (RIKEN).

The interactions of T-rays with semiconductor superlattices and with vortices in Josephson junctions are under investigation. A series of novel devices such as a room-temperature operating parametric amplifier of T-rays and a Josephson junction-based T-pump generator have been proposed. We also study spontaneous symmetry-breaking, dynamic chaos and ratchet effects in T-driven nanostructures.

The ideas are presented to the Department in a Landau-style discussion seminar.

Fig 4. Reflection of radiation from a vortex lattice	Fig 5. Schematic view of a semiconductor superlattice in electric and magnetic fields
Fig 6. Two projections of an electron trajectory in the above superlattice. Colour denotes time.
Fig 7. Regions of chaos (green) and rectification of T-wave (red) in a lateral superlattice
Fig 8. Magnetic field distribution in Josephson vortex lines. Shape waves (solitons on solitons) are seen propagating along the lines.

Some animations

• Fluxtronics
• Metamaterials as resonators
• MQT
• Nonlinear Josephson plasma waves
• AC lensing of vortices
• DC lensing of vortices (continuous)
• DC lensing of vortices (stages)
• Waveguides

In the news

Scientists control super fast frequencies by using high temperature superconductors April 2005

Dilating time with superconductors

Some recent theses

• Dmitry R Gulevich,Tunneling and Switching phenomena in Superconducting Quantum Dots and Josephson Junctions, 2006 (supervisor Kusmartsev)
• D Michael Forrester, Novel phenomena in arrays of Josephson junctions, 2007 (supervisor Kusmartsev)
• Hanaa Hassan, Flux cloning in a stack of Josephson Junctions, in progress (supervisor Kusmartsev)

Contacts

• Kirill Alekseev
• Alexander Balanov
• Boris Chesca
• Marat Gaifullin
• Dmitry Gulevich
• Feo Kusmartsev
• Alexander Rakhmanov
• Sergey Savel'ev

For further information

M.T. Greenaway, A.G. Balanov, E. Schöll, and T.M. Fromhold, Controlling and enhancing terahertz collective electron dynamics in superlattices by chaos-assisted miniband transport , Phys Rev B 80 205318 (2009) (featured in PRB Kaleidoscope images: November 2009. )

Timo Hyart, Jussi Mattas, and Kirill N. Alekseev , Model of the Influence of an External Magnetic Field on the Gain of Terahertz Radiation from Semiconductor Superlattices , Phys Rev Lett 103 117401 (2009)

Andriy V. Moskalenko, Sergey N. Gordeev, Olivia F. Koentjoro, Paul R. Raithby, Robert W. French, Frank Marken, and Sergey E. Savel'ev3, Nanomechanical electron shuttle consisting of a gold nanoparticle embedded within the gap between two gold electrodes , Phys Rev B 79 241403(R) (2009) (featured by Physics World and Nanotechweb )

Timo Hyart, Natalia V. Alexeeva, Jussi Mattas, and Kirill N. Alekseev, Terahertz Bloch Oscillator with a Modulated Bias , Phys Rev Lett 102 140405 (2009)

V R Misko, S Savel'ev, A L Rakhmanov and F Nori, Nonuniform Self-Organized Dynamical States in Superconductors with Periodic Pinning, Phys Rev Lett 96 127004 (2006)

J Hizanidis, A Balanov, A Amann and E Schöll, Noise-Induced Front Motion: Signature of a Global Bifurcation, Phys Rev Lett 96 244104 (2006)

D R Gulevich and F V Kusmartsev, Flux Cloning in Josephson Transmission Lines, Phys Rev Lett 97 017004 (2006)

A V Kats, S Savel'ev, V A Yampol'skii and F Nori, Left-Handed Interfaces for Electromagnetic Surface Waves, Phys Rev Lett 98 073901 (2007)

S Savel'ev, A L Rakhmanov and F Nori, Quantum Terahertz Electrodynamics and Macroscopic Quantum Tunneling in Layered Superconductors, Phys Rev Lett 98 077002 (2007)

K Yu Bliokh, Yu P Bliokh, S Savel'ev and F Nori, Semiclassical Dynamics of Electron Wave Packet States with Phase Vortices, Phys Rev Lett 99 190404 (2007)

S Ooi, S Savel'ev, M B Gaifullin, T Mochiku, K Hirata and F Nori, Nonlinear Nanodevices Using Magnetic Flux Quanta, Phys Rev Lett 99 207003 (2007)

T Hyart, N V Alexeeva, A Leppanen and K N Alekseev, THz parametric gain in semiconductor superlattices in the absence of electric domains, Appl Phys Lett 89 132105 (2006)

T Hyart, A V Shorokhov and K N Alekseev, Theory of Parametric Amplification in Superlattices, Phys Rev Lett 98 220404 (2007)

K N Alekseev, E H Cannon, J C McKinney, F V Kusmartsev and D K Campbell, Spontaneous DC Current Generation in Resistively Shunted Semiconductor Superlattice Driven by THz-field, Phys Rev Lett 80 2669 (1998)

K N Alekseev, E H Cannon, F V Kusmartsev and D K Campbell, Integer and unquantized dc voltage generation in THz-driven semiconductor superlattices, Europhys Lett 56 842 (2001)

K N Alekseev, G P Berman, D K Campbell, E H Cannon, and M C Cargo, Dissipative chaos in semiconductor superlattices, Phys Rev B 54 10625 (1996)

K N Alekseev, P Pietiläinen , J Isohätälä, A Zharov and F V Kusmartsev, Chaos and rectification of electromagnetic wave in a lateral semiconductor superlattice, Europhys Lett 65 292 (2005)

K N Alekseev, M V. Erementchouk and F V. Kusmartsev, Direct current generation due to wave mixing in semiconductors, Europhys Lett 47, 595 (1999)

Return to research page