Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Comparing the Linewidths from Single-Pass SPDC and Singly-Resonant Cavity SPDC



Oliver T. Slattery, Lijun Ma, Paulina S. Kuo, Xiao Tang


Spontaneous parametric down-conversion (SPDC) is a common method to generate entangled photon pairs for use in quantum communications. The generated single photon linewidth is a critical issue for photon-atom interactions in quantum memory applications. We compare the linewidths of greatly non-degenerate single photon pairs from SPDC generated in the single-pass case and the singly-resonant cavity case. For a 6 mm periodically poled lithium niobate (PPLN) crystal, the linewidth of the generated signal photons is reduced from 1 THz in the single pass case to tens of MHz in the singly-resonant cavity case, while the brightness within the modal lineiwdth is increased by a factor of the cavity finesse, though the overall SPDC generation rate remains unchanged.
Proceedings Title
Quantum Communications and Quantum Imaging XII
Conference Dates
July 9-14, 2015
Conference Location
San Diego, CA


cavity narrowed SPDC, singly-resonant SPDC cavity


Slattery, O. , Ma, L. , Kuo, P. and Tang, X. (2015), Comparing the Linewidths from Single-Pass SPDC and Singly-Resonant Cavity SPDC, Quantum Communications and Quantum Imaging XII, San Diego, CA, [online], (Accessed April 21, 2024)
Created September 3, 2015, Updated November 10, 2018