اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدHeralded quantum memory for single-photon polarization qubits
592
0
0.0
(
0
)
اسأل ChatGPT حول البحث
ﻻ يوجد ملخص باللغة العربية
We propose a scheme to implement a heralded quantum memory for single-photon polarization qubits with a single atom trapped in an optical cavity. In this scheme, an injected photon only exchanges quantum state with the atom, so that the heralded storage can be achieved by detecting the output photon. We also demonstrate that the scheme can be used for realizing the heralded quantum state transfer, exchange and entanglement distribution between distant nodes. The ability to detect whether the operation has succeeded or not is crucial for practical application.
قيم البحث
اقرأ أيضاً
Photon-based quantum information processing promises new technologies including optical quantum computing, quantum cryptography, and distributed quantum networks. Polarization-encoded photons at telecommunication wavelengths provide a compelling plat
form for practical realization of these technologies. However, despite important success towards building elementary components compatible with this platform, including sources of entangled photons, efficient single photon detectors, and on-chip quantum circuits, a missing element has been atomic quantum memory that directly allows for reversible mapping of quantum states encoded in the polarization degree of a telecom-wavelength photon. Here we demonstrate the quantum storage and retrieval of polarization states of heralded single-photons at telecom-wavelength by implementing the atomic frequency comb protocol in an ensemble of erbium atoms doped into an optical fiber. Despite remaining limitations in our proof-of-principle demonstration such as small storage efficiency and storage time, our broadband light-matter interface reveals the potential for use in future quantum information processing.
A quantum internet connects remote quantum processors that need interact and exchange quantum signals over a long distance through photonic channels. However, these quantum nodes are usually composed of quantum systems with emitted photons unsuitable
for long-distance transmission. Therefore, quantum wavelength conversion to telecom is crucial for long-distance quantum networks based on optical fiber. Here we propose wavelength conversion devices for single-photon polarization qubits using continuous variable quantum teleportation, which can efficiently convert qubits between near-infrared (780/795 nm suitable for interacting with atomic quantum nodes) and telecom wavelength (1300-1500 nm suitable for long-distance transmission). The teleportation uses entangled photon sources (i.e., non-degenerate two-mode squeezed state) that can be generated by four-wave mixing in rubidium atomic vapor cells, with a diamond configuration of atomic transitions. The entangled fields can be emitted in two orthogonal polarizations with locked relative phase, making them especially suitable for interfacing with single-photon polarization qubits. Our work paves the way for the realization of long-distance quantum networks.
Single-photon sources (SPSs) are mainly characterized by the minimum value of their second-order coherence function, viz. their $g^{(2)}$ function. A precise measurement of $g^{(2)}$ may, however, require high time-resolution devices, in whose absenc
e, only time-averaged measurements are accessible. These time-averaged measures, standing alone, do not carry sufficient information for proper characterization of SPSs. Here, we develop a theory, corroborated by an experiment, that allows us to scrutinize the coherence properties of heralded SPSs that rely on continuous-wave parametric down-conversion. Our proposed measures and analysis enable proper standardization of such SPSs.
Single photon source represent a fundamental building block for optical implementations of quantum information tasks ranging from basic tests of quantum physics to quantum communication and high-resolution quantum measurement. In this paper we invest
igate the performance of a multiplexed system based on asymmetric configuration of multiple heralded single photon sources. {To compare the effectiveness of different designs we introduce a single-photon source performance index that is based on the value of single photon probability required to achieve a guaranteed signal to noise ratio.} The performance and scalability comparison with both currently existing multiple-source architectures and faint laser configurations reveals an advantage the proposed scheme offers in realistic scenarios. This analysis also provides insights on the potential of using such architectures for integrated implementation.
Here we show an ultra-low noise regime of operation in a simple quantum memory in warm Rb atomic vapor. By modelling the quantum dynamics of four-level room temperature atoms, we achieve fidelities >90% for single-photon level polarization qubits, cl
early surpassing any classical strategy exploiting the non-unitary memory efficiency. This is the first time such important threshold has been crossed with a room temperature device. Additionally we also show novel experimental techniques capable of producing fidelities close to unity. Our results demonstrate the potential of simple, resource-moderate experimental room temperature quantum devices.
سجل دخول لتتمكن من نشر تعليقات
التعليقات
جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
