MARC보기
LDR00000nam u2200205 4500
001000000433291
00520200225133333
008200131s2019 ||||||||||||||||| ||eng d
020 ▼a 9781085586467
035 ▼a (MiAaPQ)AAI13864305
040 ▼a MiAaPQ ▼c MiAaPQ ▼d 247004
0820 ▼a 530
1001 ▼a Hu, Yichen.
24510 ▼a Studies on Fractionalization and Topology in Strongly Correlated Systems from Zero to Two Dimensions.
260 ▼a [S.l.]: ▼b University of Pennsylvania., ▼c 2019.
260 1 ▼a Ann Arbor: ▼b ProQuest Dissertations & Theses, ▼c 2019.
300 ▼a 195 p.
500 ▼a Source: Dissertations Abstracts International, Volume: 81-02, Section: B.
500 ▼a Advisor: Kane, Charles L.
5021 ▼a Thesis (Ph.D.)--University of Pennsylvania, 2019.
506 ▼a This item must not be sold to any third party vendors.
520 ▼a The interplay among symmetry, topology and condensed matter systems has deepened our understandings of matter and lead to tremendous recent progresses in finding new topological phases of matter such as topological insulators, superconductors and semi-metals. Most examples of the aforementioned topological materials are free fermion systems, in this thesis, however, we focus on their strongly correlated counterparts where electron-electron interactions play a major role. With interactions, exotic topological phases and quantum critical points with fractionalized quantum degrees of freedom emerge. In the first part of this thesis, we study the problem of resonant tunneling through a quantum dot in a spinful Luttinger liquid. It provides the simplest example of a (0+1)d system with symmetry-protected phase transitions. We show that the problem is equivalent to a two channel SU(3) Kondo problem and can be mapped to a quantum Brownian motion model on a Kagome lattice. Utilizing boundary conformal field theory, we find the universal peak conductance and compute the scaling behavior of the resonance line-shape.For the second part, we present a model of interacting Majorana fermions that describes a superconducting phase with a topological order characterized by the Fibonacci topological field theory. Our theory is based on a SO(7)1 = SO(7)1/(G2)1 x (G2)1 coset construction and implemented by a solvable two-dimensional network model. In addition, we predict a closely related ''anti-Fibonacci'' phase, whose topological order is characterized by the tricritical Ising model. Finally, we propose an interferometer that generalizes the Z2 Majorana interferometer and directly probes the Fibonacci non-Abelian statistics.For the third part, we argue that a correlated fluid of electrons and holes can exhibit fractional quantum Hall effects at zero magnetic field. We first show that a Chern insulator can be realized as a free fermion model with p-wave(m = 1) excitonic pairing. Its ground state wavefunction is then worked out and generalized to m > 1. We give several pieces of evidence that this conjectured wavefunction correctly describes a topological phase, dubbed ''fractional excitonic insulator'', within the same universality class as the corresponding Laughlin state at filling 1/m. We present physical arguments that gapless states with higher angular momentum pairing between energy bands are conducive to forming the fractional excitonic insulator in the presence of repulsive interactions. Without interactions, these gapless states appear at topological phase transitions which separate the trivial insulator from a Chern insulator with higher Chern number. Since the nonvanishing density of states at these higher angular momentum band inversion transitions can give rise to interesting many-body effects, we introduce a series of minimal lattice models realizations in two dimensions. We also study the effect of rotational symmetry broken electron-hole exciton condensation in our lattice models using mean field theory.
590 ▼a School code: 0175.
650 4 ▼a Condensed matter physics.
650 4 ▼a Physics.
690 ▼a 0611
690 ▼a 0605
71020 ▼a University of Pennsylvania. ▼b Physics and Astronomy.
7730 ▼t Dissertations Abstracts International ▼g 81-02B.
773 ▼t Dissertation Abstract International
790 ▼a 0175
791 ▼a Ph.D.
792 ▼a 2019
793 ▼a English
85640 ▼u http://www.riss.kr/pdu/ddodLink.do?id=T15491008 ▼n KERIS ▼z 이 자료의 원문은 한국교육학술정보원에서 제공합니다.
980 ▼a 202002 ▼f 2020
990 ▼a ***1816162
991 ▼a E-BOOK