On Fractionalization
edited
This page is a summary of the discussions during the Fractionalization Phenomena session.
Talk: X…
This page is a summary of the discussions during the Fractionalization Phenomena session.
Talk: X. L. Qi
How many mass terms can you generate on edge of QSH system from a 3 component magnetic field? Without disorder it seems like you only get two possible mass terms. With disorder the answer is unknown currently, but in that case you can probably get 3 .
It is difficult to measure exactly half charge (e/2) much easier to measure a charge difference of e/2.
Can you insert generic spin flux without closing the bulk energy gap? In general no, but maybe the set of points where the gap closes has measure zero.
Does the QSH edge have fractional excitations? Yes and no, if you externally impose a magnetic domain wall then no. If interactions are string enough to spontaneously break time-reversal symmetry then it is possible to have e/2 charged "domain-wall" excitations.
Compare spin-charge separation, with Kane and Fu work on Z_2 pumping.
What is quantized in quantum spin Hall?
Talk: C. Kallin
What is the dynamics of the relative phase? It is gapped by a Higgs mechanism.
Relation between S_z conservation and instantons.
There are 2 U(1) phases in each layer.
Mass generation for 1d fermions on edge given by coupling to a U(1) field.
Is there any coupling between spinons and a physical electro-magnetic field? Possibly a small coupling due to a finite system size?
The topological mott insulator paper, and this model start from interactions with no spin-orbit coupling and dynamically generate it. What about starting from interactions + spin orbit coupling and looking for phases of matter?
Talk: Y. Hatsugai
Talk: Y. Oreg
Can you think about it as similar to QSH? Not exactly because fractional charge will depend on electron-electron interactions.
Talk: A. Vishwanath
What happens in the case \nu_0=1 but \nu_1\nu_2\nu_3= (000)? This is a strong topological insulator with dirac node near \Gamma point in k-space.
Can disorder and perturbations destroy the dislocations? Can shrink to zero size, but they will act like vortices.
Can you imagine a case where these defects proliferate?
Loops that are closed and isolated do not have exact zero modes.
Can you get more than one set of modes?
For quantum Hall they have to always have a partner defect, cannot exist alone (Fermion doubling problem).
Schedule
edited
... Laurens Molenkamp: QSH effect and ballistic Spin Hall effect in HgTe quantum wells
Jairo Sino…
...
Laurens Molenkamp: QSH effect and ballistic Spin Hall effect in HgTe quantum wells
Jairo Sinova: Spin-injection Hall effect: a new member of the spintronic family Ivar Martin: Quantum Valley vs. Quantum Spin Hall effect; Spontaneous Quantum Charge Hall effect in itinerant chiral 2D magnets
Ewelina Hankiewicz: Ballistic Spin Hall effect
14:00
Aud
Discussion continue morning discussion
Fri Dec 19
10:00
Aud
Conference summary
TBAIvar Martin: Quantum Valley vs. Quantum Spin Hall effect; Spontaneous Quantum Charge Hall effect in itinerant chiral 2D magnets
Ewelina Hankiewicz: Ballistic Spin Hall effect
Charlie Kane : Conference Summary
Schedule
edited
... David Awschalom: Imaging electrical spin generation and spin Hall dynamics in semiconductors
…
...
David Awschalom: Imaging electrical spin generation and spin Hall dynamics in semiconductors
Laurens Molenkamp: QSH effect and ballistic Spin Hall effect in HgTe quantum wells
Jairo Sinova: Spin-injection Hall effect: a new member of the spintronic family
Ivar Martin: Quantum Valley vs. Quantum Spin Hall effect; Spontaneous Quantum Charge Hall effect in itinerant chiral 2D magnets
Ewelina Hankiewicz: Ballistic Spin Hall effect
Schedule
edited
... Leader: Andre Bernevig
Shuichi Murakami: Quantum spin Hall effect and bismuth ultrathin films…
...
Leader: Andre Bernevig
Shuichi Murakami: Quantum spin Hall effect and bismuth ultrathin films
...
of topological insultorsinsulators
Congjun Wu: Orbital analogue of quantum anomalous Hall effect in p-band systems
14:00
...
Discussion
Related Topics
Qian Niu: Polarization as a Chern Simons field
Ying Ran:A continuous phase transition between antiferromagnet and superconductivity: application of QSH physics in strongly correlated system
Thu Dec 18
Schedule
edited
... Leader: Andre Bernevig
Shuichi Murakami: Quantum spin Hall effect and bismuth ultrathin films…
...
Leader: Andre Bernevig
Shuichi Murakami: Quantum spin Hall effect and bismuth ultrathin films
Zhong FangFang: First Principles Calculations of TI's
Congjun Wu: Orbital analogue of quantum anomalous Hall effect in p-band systems
14:00