Entanglement of macroscopically distinct states of light

Schrödinger’s famous Gedankenexperiment has inspired multiple generations of physicists to think about apparent paradoxes that arise when the logic of quantum physics is applied to macroscopic objects. The development of quantum technologies enabled us to produce physical analogues of Schrödinger’s cats, such as superpositions of macroscopically distinct states as well as entangled states of microscopic and macroscopic entities. Here we take one step further and prepare an optical state which, in Schrödinger’s language, is equivalent to a superposition of two cats, one of which is dead and the other alive, but it is not known in which state each individual cat is. Specifically, the alive and dead states are, respectively, the displaced single photon and displaced vacuum (coherent state), with the magnitude of displacement being on a scale of 10^8 photons. These two states have significantly different photon statistics and are therefore macroscopically distinguishable

Entanglement and teleportation between polarization and wave-like encodings of an optical qubit

Light is an irreplaceable means of communication among various quantum information processing and storage devices. Due to their different physical nature, some of these devices couple more strongly to discrete, and some to continuous degrees of freedom of a quantum optical wave. It is therefore desirable to develop a technological capability to interconvert quantum information encoded in these degrees of freedom. Here we generate and characterize an entangled state between a dual-rail (polarization-encoded) single-photon qubit and a qubit encoded as a superposition of opposite-amplitude coherent states. We furthermore demonstrate the application of this state as a resource for the interfacing of quantum information between these encodings. In particular, we show teleportation of a polarization qubit onto a freely propagating continuous-variable qubit

Entangled resource for interfacing single- and dual-rail optical qubits

Today's most widely used method of encoding quantum information in optical qubits is the dual-rail basis, often carried out through the polarisation of a single photon. On the other hand, many stationary carriers of quantum information – such as atoms – couple to light via the single-rail encoding in which the qubit is encoded in the number of photons. As such, interconversion between the two encodings is paramount in order to achieve cohesive quantum networks. In this paper, we demonstrate this by generating an entangled resource between the two encodings and using it to teleport a dual-rail qubit onto its single-rail counterpart. This work completes the set of tools necessary for the interconversion between the three primary encodings of the qubit in the optical field: single-rail, dual-rail and continuous-variable

Pharmacodynamic genetic polymorphisms affect adverse drug reactions of haloperidol in patients with alcohol-use disorder

Mikhail Sergeevich Zastrozhin,1,2 Vadim Markovich Brodyansky,3 Valentin Yurievich Skryabin,4 Elena Anatolievna Grishina,5 Dmitry Vladimirovich Ivashchenko,5 Kristina Anatolievna Ryzhikova,5 Ludmila Mikhaylovna Savchenko,1 Alexander Olegovich Kibitov,3 Evgeny Alekseevich Bryun,1,4 Dmitry Alekseevich Sychev6 1Department of Addictology, Russian Medical Academy of Continuous Professional Education of the Ministry of Health of the Russian Federation, Moscow, Russia; 2Moscow Research and Practical Centre on Addictions of the Moscow Department of Healthcare, Center for the Prevention of Dependent Behavior, Moscow, Russia; 3Federal Medical Research Centre of Psychiatry and Addictology, Laboratory of Molecular Genetics, Moscow, Russia; 4Moscow Research and Practical Centre on Addictions of the Moscow Department of Healthcare, Department of Addictology, Moscow, Russia; 5Russian Medical Academy of Continuous Professional Education of the Ministry of Health of the Russian Federation, Research Centre, Moscow, Russia; 6Russian Medical Academy of Continuous Professional Education of the Ministry of Health of the Russian Federation, Department of Clinical Pharmacology and Therapy, Moscow, Russia Background: Antipsychotic action of haloperidol is due to blockade of D2 receptors in the mesolimbic dopamine pathway, while the adverse drug reactions are associated with striatal D2 receptor blockade. Contradictory data concerning the effects of genetic polymorphisms of genes encoding these receptors and associated structures (catechol-O-methyltransferase [COMT], glycine transporter and gene encoding the density of D2 receptors on the neuronal membrane) are described.Objective: The objectives of this study were to evaluate the correlation between DRD2, SLC6A3 (DAT) and COMT genetic polymorphisms and to investigate their effect on the development of adverse drug reactions in patients with alcohol-use disorder who received haloperidol.Patients and methods: The study included 64 male patients (average age 41.38 ± 10.14 years, median age 40 years, lower quintile [LQ] 35 years, upper quintile [UQ] 49 years). Bio-Rad CFX Manager™ software and “SNP-Screen” sets of “Syntol” (Russia) were used to determine polymorphisms rs4680, rs1800497, rs1124493, rs2242592, rs2298826 and rs2863170. In every “SNP-Screen” set, two allele-specific hybridizations were used, which allowed to determine two alleles of studied polymorphism separately on two fluorescence channels.Results: Results of this study detected a statistically significant difference in the adverse drug reaction intensity in patients receiving haloperidol with genotypes 9/10 and 10/10 of polymorphic marker SLC6A3 rs28363170. In patients receiving haloperidol in tablets, the increases in the UKU Side-Effect Rating Scale (UKU) score of 9.96 ± 2.24 (10/10) versus 13 ± 2.37 (9/10; p < 0.001) and in the Simpson-Angus Scale (SAS) score of 5.04 ± 1.59 (10/10) versus 6.41 ± 1.33 (9/10; p = 0.006) were revealed.Conclusion: Polymorphism of the SCL6A3 gene can affect the safety of haloperidol, and this should be taken into account during the choice of drug and its dosage regimen. Keywords: haloperidol, pharmacogenetics, DRD2, COMT, DAT, alcohol addiction, alcohol-use disorde