We investigate dissipative phase transitions in an open central spin system. In our model the central spin interacts coherently with the surrounding many-particle spin environment and is subject to coherent driving and dissipation. We develop analytical tools based on a self-consistent Holstein-Primakoff approximation that enable us to determine the complete phase diagram associated with the steady states of this system. It includes first- and second-order phase transitions, as well as regions of bistability, spin squeezing, and altered spin-pumping dynamics. Prospects of observing these phenomena in systems such as electron spins in quantum dots or nitrogen-vacancy centers coupled to lattice nuclear spins are briefly discussed.We investigate dissipative phase transitions in an open central spin system. In our model the central spin interacts coherently with the surrounding many-particle spin environment and is subject to coherent driving and dissipation. We develop analytical tools based on a self-consistent Holstein-Primakoff approximation that enable us to determine the complete phase diagram associated with the steady states of this system. It includes first- and second-order phase transitions, as well as regions of bistability, spin squeezing, and altered spin-pumping dynamics. Prospects of observing these phenomena in systems such as electron spins in quantum dots or nitrogen-vacancy centers coupled to lattice nuclear spins are briefly discussed.

arXiv:1205.3341Physical Review AJul 23, 2012345 citations

Phase Transitions In Spin Systems

Johannes Richter, S E Kreuger, DAMIAN J. J. FARNELL +1 more

Jan 1, 20010 citations

Dynamics of intrinsic optical bistability in two weakly interacting quantum systems

O. Guillot-Noël, Philippe Goldner, Didier Gourier

The dynamics of the intrinsic optical bistability (IOB) in an elementary quantum system is investigated in the situation where this system is composed of two weakly interacting subsystems. Numerical calculations have been performed for two ``real'' systems where IOB has been experimentally observed. The first situation corresponds to the electron-nuclear spin system of $\ensuremath{\beta}\ensuremath{-}{\mathrm{Ga}}_{2}{\mathrm{O}}_{3},$ where the transition between electron spin states exhibit a strong bistability. The other situation corresponds to optical transitions in ${\mathrm{Yb}}^{3+}$ pairs in ${\mathrm{CsCdBr}}_{3}:\mathrm{Yb}$ compound, where IOB has been experimentally observed. It is shown that, in addition to the classical hysteresis of the response of the system upon variation of the power of the external field, the observation of the so-called critical slowing down is a clear signature of IOB.The dynamics of the intrinsic optical bistability (IOB) in an elementary quantum system is investigated in the situation where this system is composed of two weakly interacting subsystems. Numerical calculations have been performed for two ``real'' systems where IOB has been experimentally observed. The first situation corresponds to the electron-nuclear spin system of $\ensuremath{\beta}\ensuremath{-}{\mathrm{Ga}}_{2}{\mathrm{O}}_{3},$ where the transition between electron spin states exhibit a strong bistability. The other situation corresponds to optical transitions in ${\mathrm{Yb}}^{3+}$ pairs in ${\mathrm{CsCdBr}}_{3}:\mathrm{Yb}$ compound, where IOB has been experimentally observed. It is shown that, in addition to the classical hysteresis of the response of the system upon variation of the power of the external field, the observation of the so-called critical slowing down is a clear signature of IOB.

Physical Review ADec 27, 20028 citations

Phase transitions in spin systems

van Kah Ton Leeuwen

Jan 1, 19780 citations

{\mathrm{Yb}}^{3+}

pairs in

{\mathrm{CsCdBr}}_{3}:\mathrm{Yb}

compound, where IOB has been experimentally observed. It is shown that, in addition to the classical hysteresis of the response of the system upon variation of the power of the external field, the observation of the so-called critical slowing down is a clear signature of IOB.