Entangled photon apparatus for the undergraduate laboratory

Entangled photons, nonlocality and Bell inequalities in the undergraduate laboratory

We use polarization-entangled photon pairs to demonstrate quantum nonlocality in an experiment suitable for advanced undergraduates. The photons are produced by spontaneous parametric downconversion using a violet diode laser and two nonlinear crystals. The polarization state of the photons is tunable. Using an entangled state analogous to that described in the Einstein-Podolsky-Rosen ``paradox,'' we demonstrate strong polarization correlations of the entanged photons. Bell's idea of a hidden variable theory is presented by way of an example and compared to the quantum prediction. A test of th…

A Demonstration of Quantum Key Distribution with Entangled Photons for the Undergraduate Laboratory

Now that fundamental quantum principles of indeterminacy and measurement have become the basis of new technologies that provide secrecy between two communicating parties, there is a need to provide teaching laboratories that illustrate how these technologies work. In this article we describe a laboratory exercise in which students perform quantum key distribution with single photons, and see how the secrecy of the communication is ensured by the principles of quantum superposition and state projection. We used a table-top apparatus, similar to those used in correlated-photon undergraduate labo…

用于金刚石中单个氮-空位中心量子实验的教学实验装置

An instructional lab apparatus for quantum experiments with single nitrogen-vacancy centers in diamond

本文介绍一套用于金刚石中单个氮-空位中心量子实验的教学装置，支持单量子比特操作及电子-核自旋相互作用实验，使学生能在单学期内自主编写控制与数据分析软件，为本科量子教学提供独立资源。

Delayed-choice quantum eraser for the undergraduate laboratory

In a delayed-choice quantum eraser, interference fringes are obtained by erasing which-way information after the interfering particle has already been irreversibly detected. Following an introductory review of delayed-choice experiments and quantum erasure, we describe the experimental realization of an optical delayed-choice quantum eraser, suitable for advanced undergraduates, based on polarization-entangled pairs of single photons. In our experiment, the delay of the erasure is implemented using two different setups. The first setup employs an arrangement of mirrors to increase the optical …

在本科实验室中测量光量子态的 Wigner 函数

Measuring Wigner functions of quantum states of light in the undergraduate laboratory

本文介绍了一项在本科实验室测量光量子态 Wigner 分布函数的教育活动，学生通过预对准实验装置和定制图形界面重建 Wigner 函数，并加入模拟数据分析功能以支持疫情下的量子光学远程学习。

用于本科实验室的光纤多功能Hong-Ou-Mandel干涉实验

A Versatile Hong-Ou-Mandel Interference Experiment in Optical Fiber for the Undergraduate Laboratory

本文提出一种基于光纤和商用双光子源的HOM干涉实验装置，以熔融光纤耦合器替代传统分束器，降低对准难度并支持温度调控频率简并性，适合本科实验室研究相干长度与干涉可见度。