Seminars & Lectures
| * TITLE | Spin liquids in two dimensional correlated Dirac electrons | ||||||
|---|---|---|---|---|---|---|---|
| * SPEAKERS | |||||||
|
|||||||
| * HOST(Applicant) | |||||||
|
|||||||
| * DATE / TIME | 2012-02-20, 4:00PM | ||||||
| * PLACE | 503 Conference room, APCTP Headquarters | ||||||
| * ABSTRACT | |||||||
| We reveal that local interactions in two dimensional correlated Dirac electrons allow novel spin liquids between the semi-metal and antiferromagnetic Mott insulating phases, identified with algebraic spin liquid and Z$_{2}$ spin liquid, respectively. The algebraic spin liquid can be regarded as the two dimensional realization of one dimensional spin dynamics, where antiferromagnetic correlations show exactly the same power-law dependence as valence bond correlations. Nature of the Z$_{2}$ spin liquid turns out to be $d + i d\\\'$ singlet pairing, but time reversal symmetry is preserved, taking $d + i d\\\'$ in one valley and $d - i d\\\'$ in the other valley. Quantum phase transitions among the semi-metal, algebraic spin liquid, and Z$_{2}$ spin liquid are shown to be continuous while the transition from the Z$_{2}$ spin liquid to the antiferromagnetic Mott insulator turns out to be the first order. |
|||||||
