An Exact SU(2) Symmetry and Persistent Spin Helix ina Spin-orbit Coupled System

Journal Article · Mon Jan 22 00:00:00 EST 2007 · Physical Review Lettters

OSTI ID:898147

Bernevig, B A; Orenstein, J; Zhang, Shou-Cheng

Spin-orbit coupled systems generally break the spin rotation symmetry. However, for a model with equal Rashba and Dresselhauss coupling constant (the ReD model), and for the [110] Dresselhauss model, a new type of SU(2) spin rotation symmetry is discovered. This symmetry is robust against spin-independent disorder and interactions, and is generated by operators whose wavevector depends on the coupling strength. It renders the spin lifetime infinite at this wavevector, giving rise to a Persistent Spin Helix (PSH). We obtain the spin fluctuation dynamics at, and away, from the symmetry point, and suggest experiments to observe the PSH.

• Research Organization: SLAC National Accelerator Lab., Menlo Park, CA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-76SF00515
• OSTI ID: 898147
• Report Number(s): SLAC-PUB-12313; TRN: US0700572
• Journal Information: Physical Review Lettters, Journal Name: Physical Review Lettters
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
SU-2 GROUPS
COUPLING CONSTANTS
FLUCTUATIONS
LIFETIME
ROTATION
SPIN
SYMMETRY
Accelerators
ACCSYS