



@article {2814,
	title = {Kramers{\textquoteright} degeneracy for open systems in thermal equilibrium},
	journal = {Phys. Rev. B},
	volume = {105},
	year = {2022},
	month = {3/10/2022},
	pages = {L121104},
	doi = {https://doi.org/10.1103/PhysRevB.105.L121104},
	url = {https://arxiv.org/abs/2105.02888},
	author = {Simon Lieu and Max McGinley and Oles Shtanko and Nigel R. Cooper and Alexey V. Gorshkov}
}
@article {1994,
	title = {Keyring models: an approach to steerability},
	journal = {Journal of Mathematical Physics},
	volume = {59},
	year = {2018},
	month = {2018/01/02},
	pages = {022103},
	abstract = {<p>If a measurement is made on one half of a bipartite system then, conditioned on the outcome, the other half has a new reduced state. If these reduced states defy classical explanation \&mdash; that is, if shared randomness cannot produce these reduced states for all possible measurements \&mdash; the bipartite state is said to be steerable. Determining which states are steerable is a challenging problem even for low dimensions. In the case of two-qubit systems a criterion is known for T-states (that is, those with maximally mixed marginals) under projective measurements. In the current work we introduce the concept of keyring models \&mdash; a special class of local hidden state model. When the measurements made correspond to real projectors, these allow us to study steerability beyond T-states. Using keyring models, we completely solve the steering problem for real projective measurements when the state arises from mixing a pure two-qubit state with uniform noise. We also give a partial solution in the case when the uniform noise is replaced by independent depolarizing channels. Our results imply that Werner states, which are a special case of the previous states, are unsteerable under real projective measurements if and only if their efficiency is at most 2/π.</p>},
	doi = {10.1063/1.5006199},
	url = {http://aip.scitation.org/doi/full/10.1063/1.5006199},
	author = {Carl Miller and Roger Colbeck and Yaoyun Shi}
}
@article {1695,
	title = {Kaleidoscope of quantum phases in a long-range interacting spin-1 chain},
	journal = {Physical Review B},
	volume = {93},
	year = {2016},
	month = {2016/05/11},
	pages = {205115},
	abstract = {Motivated by recent trapped-ion quantum simulation experiments, we carry out a comprehensive study of the phase diagram of a spin-1 chain with XXZ-type interactions that decay as 1/rα, using a combination of finite and infinite-size DMRG calculations, spin-wave analysis, and field theory. In the absence of long-range interactions, varying the spin-coupling anisotropy leads to four distinct phases: a ferromagnetic Ising phase, a disordered XY phase, a topological Haldane phase, and an antiferromagnetic Ising phase. If long-range interactions are antiferromagnetic and thus frustrated, we find primarily a quantitative change of the phase boundaries. On the other hand, ferromagnetic (non-frustrated) long-range interactions qualitatively impact the entire phase diagram. Importantly, for α≲3, long-range interactions destroy the Haldane phase, break the conformal symmetry of the XY phase, give rise to a new phase that spontaneously breaks a U(1) continuous symmetry, and introduce an exotic tricritical point with no direct parallel in short-range interacting spin chains. We show that the main signatures of all five phases found could be observed experimentally in the near future.
},
	doi = {http://dx.doi.org/10.1103/PhysRevB.93.205115},
	url = {http://arxiv.org/abs/1510.02108},
	author = {Zhe-Xuan Gong and Mohammad F. Maghrebi and Anzi Hu and Michael Foss-Feig and Philip Richerme and Christopher Monroe and Alexey V. Gorshkov}
}
@article {1177,
	title = {Kitaev chains with long-range pairing},
	journal = {Physical Review Letters},
	volume = {113},
	year = {2014},
	month = {2014/10/9},
	abstract = {  We propose and analyze a generalization of the Kitaev chain for fermions with
long-range $p$-wave pairing, which decays with distance as a power-law with
exponent $\alpha$. Using the integrability of the model, we demonstrate the
existence of two types of gapped regimes, where correlation functions decay
exponentially at short range and algebraically at long range ($\alpha > 1$) or
purely algebraically ($\alpha < 1$). Most interestingly, along the critical
lines, long-range pairing is found to break conformal symmetry for sufficiently
small $\alpha$. This is accompanied by a violation of the area law for the
entanglement entropy in large parts of the phase diagram in the presence of a
gap, and can be detected via the dynamics of entanglement following a quench.
Some of these features may be relevant for current experiments with cold atomic
ions.
},
	doi = {10.1103/PhysRevLett.113.156402},
	url = {http://arxiv.org/abs/1405.5440v2},
	author = {Davide Vodola and Luca Lepori and Elisa Ercolessi and Alexey V. Gorshkov and Guido Pupillo}
}
@article {1175,
	title = {Kitaev honeycomb and other exotic spin models with polar molecules},
	journal = {Molecular Physics},
	volume = {111},
	year = {2013},
	month = {2013/01/01},
	pages = {1908 - 1916},
	abstract = {  We show that ultracold polar molecules pinned in an optical lattice can be
used to access a variety of exotic spin models, including the Kitaev honeycomb
model. Treating each molecule as a rigid rotor, we use DC electric and
microwave fields to define superpositions of rotational levels as effective
spin degrees of freedom, while dipole-dipole interactions give rise to
interactions between the spins. In particular, we show that, with sufficient
microwave control, the interaction between two spins can be written as a sum of
five independently controllable Hamiltonian terms proportional to the five
rank-2 spherical harmonics Y_{2,q}(theta,phi), where (theta,phi) are the
spherical coordinates of the vector connecting the two molecules. To
demonstrate the potential of this approach beyond the simplest examples studied
in [S. R. Manmana et al., arXiv:1210.5518v2], we focus on the realization of
the Kitaev honeycomb model, which can support exotic non-Abelian anyonic
excitations. We also discuss the possibility of generating spin Hamiltonians
with arbitrary spin S, including those exhibiting SU(N=2S+1) symmetry.
},
	doi = {10.1080/00268976.2013.800604},
	url = {http://arxiv.org/abs/1301.5636v1},
	author = {Alexey V. Gorshkov and Kaden R. A. Hazzard and Ana Maria Rey}
}
