@inproceedings{42032,
  author       = {{Jöns, Klaus D. and  Hafenbrak, R and Singh, R and Ding, F and  Plumhof, J.D and Rastelli, A and  Schmidt, O.G and Bester, G and Michler, P}},
  pages        = {{217402}},
  title        = {{{Dependence of the Redshifted and Blueshifted Photoluminescence Spectra of Single In(x)Ga(1−x)As/GaAs Quantum Dots on the Applied Uniaxial Stress}}},
  volume       = {{107}},
  year         = {{2011}},
}

@article{8178,
  abstract     = {{In [Piani et al., PRL106 (2011) 220403], an activation protocol was introduced which maps the general non-classical (multipartite) correlations between given systems into bipartite entanglement between the systems and local ancillae by means of a potentially highly entangling interaction. Here, we study how this activation protocol can be used to entangle the starting systems themselves via entanglement swapping through a measurement on the ancillae. Furthermore, we bound the relative entropy of quantumness (a naturally arising measure of non-classicality in the scheme of Piani et al. above) for a special class of separable states, the so-called classical–quantum states. In particular, we fully characterize the classical–quantum two-qubit states that are maximally non-classical.}},
  author       = {{Gharibian, Sevag and PIANI, MARCO and ADESSO, GERARDO and CALSAMIGLIA, JOHN and HORODECKI, PAWEŁ}},
  issn         = {{0219-7499}},
  journal      = {{International Journal of Quantum Information}},
  number       = {{07n08}},
  pages        = {{1701--1713}},
  publisher    = {{World Scientific Pub Co Pte Lt}},
  title        = {{{Characterizing Quantumness via Entanglement Creation}}},
  doi          = {{10.1142/s0219749911008258}},
  volume       = {{09}},
  year         = {{2011}},
}

@inproceedings{8176,
  abstract     = {{Approximation algorithms for classical constraint satisfaction problems are one of the main research areas in theoretical computer science. Here we define a natural approximation version of the QMA-complete local Hamiltonian problem and initiate its study. We present two main results. The first shows that a non-trivial approximation ratio can be obtained in the class NP using product states. The second result (which builds on the first one), gives a polynomial time (classical) algorithm providing a similar approximation ratio for dense instances of the problem. The latter result is based on an adaptation of the "exhaustive sampling method" by Arora et al. [J. Comp. Sys. Sci. 58, p.193 (1999)] to the quantum setting, and might be of independent interest.}},
  author       = {{Gharibian, Sevag and Kempe, Julia}},
  booktitle    = {{IEEE Annual Conference on Computational Complexity (CCC 2011)}},
  isbn         = {{9781457701795}},
  location     = {{San Jose, USA}},
  publisher    = {{IEEE}},
  title        = {{{Approximation Algorithms for QMA-Complete Problems}}},
  doi          = {{10.1109/ccc.2011.15}},
  year         = {{2011}},
}

@article{8177,
  abstract     = {{We devise a protocol in which general nonclassical multipartite correlations produce a physically relevant effect, leading to the creation of bipartite entanglement. In particular, we show that the relative entropy of quantumness, which measures all nonclassical correlations among subsystems of a quantum system, is equivalent to and can be operationally interpreted as the minimum distillable entanglement generated between the system and local ancillae in our protocol. We emphasize the key role of state mixedness in maximizing nonclassicality: Mixed entangled states can be arbitrarily more nonclassical than separable and pure entangled states.}},
  author       = {{Piani, Marco and Gharibian, Sevag and Adesso, Gerardo and Calsamiglia, John and Horodecki, Paweł and Winter, Andreas}},
  issn         = {{0031-9007}},
  journal      = {{Physical Review Letters}},
  number       = {{22}},
  publisher    = {{American Physical Society (APS)}},
  title        = {{{All Nonclassical Correlations Can Be Activated into Distillable Entanglement}}},
  doi          = {{10.1103/physrevlett.106.220403}},
  volume       = {{106}},
  year         = {{2011}},
}

@inproceedings{42030,
  author       = {{ Richter, D and Hafenbrak, R and Jöns, Klaus D. and Schulz, W-M and Eichfelder, M and Heldmaier, M and Roßbach, R and Jetter, M and Michler, P}},
  title        = {{{Low-density MOVPE grown InGaAs QDs exhibiting ultra-narrow single exciton linewidths}}},
  volume       = {{21}},
  year         = {{2010}},
}

@article{8179,
  abstract     = {{Given the density matrix rho of a bipartite quantum state, the quantum separability problem asks whether rho is entangled or separable. In 2003, Gurvits showed that this problem is NP-hard if rho is located within an inverse exponential (with respect to dimension) distance from the border of the set of separable quantum states. In this paper, we extend this NP-hardness to an inverse polynomial distance from the separable set. The result follows from a simple combination of works by Gurvits, Ioannou, and Liu. We apply our result to show (1) an immediate lower bound on the maximum distance between a bound entangled state and the separable set (assuming P != NP), and (2) NP-hardness for the problem of determining whether a completely positive trace-preserving linear map is entanglement-breaking.}},
  author       = {{Gharibian, Sevag}},
  journal      = {{Quantum Information & Computation}},
  number       = {{3{\&}4}},
  pages        = {{343--360}},
  title        = {{{Strong NP-hardness of the quantum separability problem}}},
  volume       = {{10}},
  year         = {{2010}},
}

@article{8180,
  abstract     = {{Given a bipartite quantum state rho with subsystems A and B of arbitrary dimensions, we study the entanglement detecting capabilities of locally noneffective, or cyclic, unitary operations [L. B. Fu, Europhys. Lett., vol. 75, pp. 1-7, 2006]. Local cyclic unitaries have the special property that they leave their target subsystem invariant. We investigate the distance between rho and the global state after local application of such unitaries as a possible indicator of entanglement. To this end, we derive and discuss closed formulae for the maximal such distance achievable for three cases of interest: (pseudo)pure quantum states, Werner states, and two-qubit states. What makes this criterion interesting, as we show here, is that it surprisingly displays behavior similar to recent anomalies observed for non-locality measures in higher dimensions, as well as demonstrates an equivalence to the CHSH inequality for certain classes of two-qubit states. Yet, despite these similarities, the criterion is not itself a non-locality measure. We also consider entanglement detection in bound entangled states.}},
  author       = {{Gharibian, Sevag and Kampermann, Hermann and Bru{\ss}, Dagmar}},
  journal      = {{Quantum Information & Computation}},
  number       = {{11}},
  pages        = {{1013--1029}},
  title        = {{{On global effects caused by locally noneffective unitary operations}}},
  volume       = {{9}},
  year         = {{2009}},
}

@article{8181,
  abstract     = {{We investigate signatures of non-classicality in quantum states, in particular, those involved in the DQC1 model of mixed-state quantum computation [Phys. Rev. Lett. 81, 5672 (1998)]. To do so, we consider two known non-classicality criteria. The first quantifies disturbance of a quantum state under locally noneffective unitary operations (LNU), which are local unitaries acting invariantly on a subsystem. The second quantifies measurement induced disturbance (MID) in the eigenbasis of the reduced density matrices. We study the role of both figures of non-classicality in the exponential speedup of the DQC1 model and compare them vis-a-vis the interpretation provided in terms of quantum discord. In particular, we prove that a non-zero quantum discord implies a non-zero shift under LNUs. We also use the MID measure to study the locking of classical correlations [Phys. Rev. Lett. 92, 067902 (2004)] using two mutually unbiased bases (MUB). We find the MID measure to exactly correspond to the number of locked bits of correlation. For three or more MUBs, it predicts the possibility of superior locking effects.}},
  author       = {{Datta, Animesh and Gharibian, Sevag}},
  issn         = {{1050-2947}},
  journal      = {{Physical Review A}},
  number       = {{4}},
  publisher    = {{American Physical Society (APS)}},
  title        = {{{Signatures of nonclassicality in mixed-state quantum computation}}},
  doi          = {{10.1103/physreva.79.042325}},
  volume       = {{79}},
  year         = {{2009}},
}

@article{37680,
  author       = {{Silberhorn, Ch. and Korolkova, N. and Leuchs, G.}},
  issn         = {{0031-9007}},
  journal      = {{Physical Review Letters}},
  keywords     = {{General Physics and Astronomy}},
  number       = {{16}},
  publisher    = {{American Physical Society (APS)}},
  title        = {{{Quantum Key Distribution with Bright Entangled Beams}}},
  doi          = {{10.1103/physrevlett.88.167902}},
  volume       = {{88}},
  year         = {{2002}},
}