1
|
Bisotto I, Kannan ES, Portal JC, Brown D, Beck TJ, Krupko Y, Jalabert L, Fujita H, Hoshi Y, Shiraki Y, Saraya T. Ratchet effect study in Si/SiGe heterostructures in the presence of asymmetrical antidots for different polarizations of microwaves. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2014; 15:045005. [PMID: 27877706 PMCID: PMC5090694 DOI: 10.1088/1468-6996/15/4/045005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 07/28/2014] [Accepted: 06/12/2014] [Indexed: 06/06/2023]
Abstract
In this work, we studied the photovoltage response of an antidot lattice to microwave radiation for different antidot parameters. The study was carried out in a Si/SiGe heterostructure by illuminating the antidot lattice with linearly polarized microwaves and recording the polarity of induced photovoltage for different angles of incidence. Our study revealed that with increased antidot density and etching depth, the polarity of induced photovoltage changed when the angle of incidence was rotated 90 degrees. In samples with large antidot density and/or a deeply etched antidot lattice, scattering was dominated by electron interaction with the asymmetrical potential created by semicircular antidots. The strong electron-electron interaction prevailed in other cases. Our study provides insight into the mechanism of interaction between microwaves and electrons in an antidot lattice, which is the key for developing an innovative ratchet-based device. Moreover, we present an original and fundamental example of antidot lattice etching through the use of a two-dimensional electron gas. This system deals with a hole lattice instead of an electron depletion in the antidot lattice region.
Collapse
Affiliation(s)
- Isabelle Bisotto
- LNCMI, UPR 3228, CNRS-INSA-UJF-UPS, BP166, F-38042 Grenoble cedex 9, France
| | - Ethirajulu S Kannan
- LNCMI, UPR 3228, CNRS-INSA-UJF-UPS, BP166, F-38042 Grenoble cedex 9, France; Department of Physics, BITS-Pilani, K K Birla, Goa Campus, Zuarinagar, Goa-403726, India
| | - Jean-Claude Portal
- LNCMI, UPR 3228, CNRS-INSA-UJF-UPS, BP166, F-38042 Grenoble cedex 9, France; Institut Universitaire de France and Institut National des Sciences Appliquées, Toulouse, F-31077 cedex 4, France
| | - Devin Brown
- Microelectronics Research Center, Georgia Institute of Technology, 791 Atlantic Drive NW, Atlanta, Georgia 30322, USA
| | - Thomas J Beck
- Microelectronics Research Center, Georgia Institute of Technology, 791 Atlantic Drive NW, Atlanta, Georgia 30322, USA
| | - Yuriy Krupko
- LNCMI, UPR 3228, CNRS-INSA-UJF-UPS, BP166, F-38042 Grenoble cedex 9, France
| | - Laurent Jalabert
- LIMMS-CNRS-IIS, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Hiroyuki Fujita
- CIRMM-IIS, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Yusuke Hoshi
- Advanced Research Laboratory, Tokyo City University, 8-15-1 Todoroki, Setagaya-ku, 158-0082 Tokyo, Japan
| | - Yasuhiro Shiraki
- Advanced Research Laboratory, Tokyo City University, 8-15-1 Todoroki, Setagaya-ku, 158-0082 Tokyo, Japan
| | - Takura Saraya
- IIS, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| |
Collapse
|
2
|
Torres M, Kunold A. Photoconductivity in AC-driven modulated two-dimensional electron gas in a perpendicular magnetic field. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2006; 18:4029-4045. [PMID: 21690755 DOI: 10.1088/0953-8984/18/16/010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In this work we study the microwave photoconductivity of a two-dimensional electron system (2DES) in the presence of a magnetic field and a two-dimensional modulation (2D). The model includes the microwave and Landau contributions in a non-perturbative exact way; the periodic potential is treated perturbatively. The Landau-Floquet states provide a convenient base with respect to which the lattice potential becomes time dependent, inducing transitions between the Landau-Floquet levels. Based on this formalism, we provide a Kubo-like formula that takes into account the oscillatory Floquet structure of the problem. The total longitudinal conductivity and resistivity exhibit strong oscillations, determined by ϵ = ω/ω(c), with ω the radiation frequency and ω(c) the cyclotron frequency. The oscillations follow a pattern with minima centred at [Formula: see text], and maxima centred at [Formula: see text], where j = 1,2,3..., δ∼1/5 is a constant shift and l is the dominant multipole contribution. Negative resistance states (NRSs) develop as the electron mobility and the intensity of the microwave power are increased. These NRSs appear in a narrow window region of values of the lattice parameter (a), around a∼l(B), where l(B) is the magnetic length. It is proposed that these phenomena may be observed in artificially fabricated arrays of periodic scatterers at the interface of ultraclean GaAs /Al(x)Ga(1-x)As heterostructures.
Collapse
Affiliation(s)
- Manuel Torres
- Instituto de Física, Universidad Nacional Autónoma de México, Apartado Postal 20-364, México Distrito Federal 01000, Mexico
| | | |
Collapse
|
3
|
Rakhlin DA. Enhanced diffusion in smoothly modulated superlattices. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2001; 63:011112. [PMID: 11304239 DOI: 10.1103/physreve.63.011112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2000] [Indexed: 05/23/2023]
Abstract
We investigate a superdiffusive behavior found in a quasiclassical model of a square-planar superlattice subjected to a perpendicular magnetic field. It is shown that certain accelerated domains are responsible for long trapping of tracers and setting them into near-ballistic motion. The mechanism of entrapment appears to be two-staged and multifractal. Relatively short trapping occurs in the vicinity of homoclinic tangles, created by intersections of stable and unstable manifolds of a hyperbolic fixed point, connected to itself. A structure of the quasitrap reveals families of multipulse solutions, doubly asymptotic to slow manifolds. The existence of orbits of this type was proved [G. Haller and S. Wiggins, Arch. Rational Mech. Anal. 130, 25 (1995)] for integrable two-degree-of-freedom Hamiltonian systems with perturbation. We describe mixing dynamics in this region and examine characteristic escape time scales. More prolonged quasitrapping is due to sticking to resonant multilayered island chains that are found to accelerate ballistic transport. Phase-space dynamics is analyzed. We successfully employ a renewal process formalism to relate Poincare recurrences and coordinate variance asymptotics for both quasitraps and also justify the use of this formalism for the specific case of gradually increasing average velocity.
Collapse
Affiliation(s)
- D A Rakhlin
- Department of Physics, New York University, 4 Washington Place, New York, New York 10003, USA
| |
Collapse
|
4
|
Iomin A. Quantum response for chaotic resonances. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 2000; 62:442-9. [PMID: 11088479 DOI: 10.1103/physreve.62.442] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/1999] [Indexed: 11/07/2022]
Abstract
Chaotic dynamics of conducting electrons in the presence of a high-frequency electromagnetic field and a constant homogeneous magnetic field is considered. It is shown that quantum fluctuations become important in this case on a time scale shorter than mean free time. Nonperturbative approach for calculation of a kinetic coefficient (conductivity) is developed. An analytical expression for the kinetic coefficient as a function of the magnetic field and a localization length is obtained. Dependence of the conductivity on the quantum localization length is studied.
Collapse
Affiliation(s)
- A Iomin
- Physics Department, Technion, Haifa 32000, Israel
| |
Collapse
|
5
|
Iomin A, Zaslavsky GM. Hierarchical structures in the phase space and fractional kinetics: II. Immense delocalization in quantized systems. CHAOS (WOODBURY, N.Y.) 2000; 10:147-152. [PMID: 12779370 DOI: 10.1063/1.166482] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Anomalous transport due to Levy-type flights in quantum kicked systems is studied. These systems are kicked rotor and kicked Harper model. It is confirmed for a kicked rotor that there exist special "magic" values of a control parameter of chaos K=K(*)=6.908 745 em leader for which an essential increasing of a localization length is obtained. Functional dependence of the localization length on both parameter of chaos and quasiclassical parameter h is studied. We also observe immense delocalization of the order of 10(9) for a kicked Harper model when a control parameter K is taken to be K(*)=6.349 972. This "magic" value corresponds to special phase space topology in the classical limit, when a hierarchical self-similar set of sticky islands emerges. The origin of the effect is of the general nature and similar immense delocalization as well as increasing of localization length can be found in other systems. (c) 2000 American Institute of Physics.
Collapse
Affiliation(s)
- A. Iomin
- Department of Physics, Technion, Haifa 32000, Israel
| | | |
Collapse
|
6
|
Iomin A, Zaslavsky GM. Immense delocalization from fractional kinetics. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1999; 60:7580-3. [PMID: 11970715 DOI: 10.1103/physreve.60.7580] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/1999] [Indexed: 04/18/2023]
Abstract
We observe immense delocalization of the order of 10(9) for a kicked Harper model when a control parameter K is taken to be K*=6.349 972. This "magic" value corresponds to special phase space topology in the classical limit, when a hierarchical self-similar set of sticky islands emerges. The origin of the effect is of the general nature and similar immense delocalization can be found in other systems.
Collapse
Affiliation(s)
- A Iomin
- Department of Physics, Technion, Haifa 32000, Israel
| | | |
Collapse
|
7
|
Knipp PA, Reinecke TL. Boundary-element method for the calculation of electronic states in semiconductor nanostructures. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:1880-1891. [PMID: 9986036 DOI: 10.1103/physrevb.54.1880] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|