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DC Transport in Two-Dimensional Electron Systems under Strong Microwave Illumination

Title: DC Transport in Two-Dimensional Electron Systems under Strong Microwave Illumination.
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Name(s): Chakraborty, Shantanu, author
Engel, Lloyd W., professor co-directing dissertation
Chiorescu, Irinel, professor co-directing dissertation
Dalal, Naresh S., university representative
Cao, Jianming, 1962-, committee member
Bonesteel, N. E., committee member
Volya, Alexander, committee member
Florida State University, degree granting institution
College of Art and Sciences, degree granting college
Department of Physics, degree granting department
Type of Resource: text
Genre: Text
Issuance: monographic
Date Issued: 2014
Publisher: Florida State University
Place of Publication: Tallahassee, Florida
Physical Form: computer
online resource
Extent: 1 online resource (109 pages)
Language(s): English
Abstract/Description: At low temperature (T) and weak magnetic field (B), two dimensional electron systems (2DES) can exhibit strong 1/B-periodic resistance oscillations on application of sufficiently strong microwave radiation. These oscillations are known as microwave induced resistance oscillations (MIROs), MIROs appearing near cyclotron resonance (CR) and its harmonics involve single photon processes and are called integer MIROs while the oscillations near CR subharmonics require multiphoton processes and are called fractional MIROs. Similar strong 1/B periodic resistance oscillations can occur due to strong dc current, and are known as Hall-field resistance oscillations (HIROs). Oscillations also occur for a combination of microwave radiation and strong dc current. In one prominent theory of MIROs, known as the displacement model , electrons make impurity-assisted transitions into higher or lower Landau levels by absorbing or emitting one or more (N) photons. In the presence of combined strong dc current and microwave radiation, electrons make transitions between Landau levels by absorbing or emitting photons followed by a space transition along the applied dc bias. The object of the dissertation is to explore how the different resistance oscillations are affected by strong microwave radiation when multiphoton processes are relevant. We used a coplanar waveguide (CPW) structure deposited on the sample, as opposed to simply placing the sample near the termination of a waveguide as is more the usual practice in this field. The CPW allows us to estimate the AC electric field (E_{AC}) at the sample. In much of the work presented in this thesis we find that higher $N$ processes supersede the competing lower N processes as microwave power is increased. We show this in the presence and in the absence of a strong dc electric field. Finally, we look at the temperature evolution of fractional MIROs to compare the origin of the fractional MIROs with that of integer MIROs.
Identifier: FSU_migr_etd-9155 (IID)
Submitted Note: A Dissertation submitted to the Department of Physics in partial fulfillment of the requirements for the degree of Doctor of Philosophy.
Degree Awarded: Fall Semester, 2014.
Date of Defense: November 13, 2014.
Bibliography Note: Includes bibliographical references.
Advisory Committee: Lloyd Engel, Professor Co-Directing Dissertation; Irinel Chiorescu, Professor Co-Directing Dissertation; Naresh Dalal, University Representative; Jianming Cao, Committee Member; Nicholas Bonesteel, Committee Member; Alexander Volya, Committee Member.
Subject(s): Condensed matter
Persistent Link to This Record: http://purl.flvc.org/fsu/fd/FSU_migr_etd-9155
Owner Institution: FSU

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Chakraborty, S. (2014). DC Transport in Two-Dimensional Electron Systems under Strong Microwave Illumination. Retrieved from http://purl.flvc.org/fsu/fd/FSU_migr_etd-9155