NuCrypt - RCS-2000 - Remote Correlation System (RCS)

RCS-2000

NuCrypt provides an easy-to-use remote correlation system (RCS) for processing and storing single photon detections. It includes all the features you need to connect distant single photon detectors and to count, correlate, or store the resulting data, as well as to generate high-speed trigger signals when particular events (typically a correlation event) occur. Clock drift and delay from channels propagating over different fibers can be accounted for, with up to four local and four remote channels correlated. The optional optical-communications (OC) channel allows two RCS’s to be connected over optical fiber and function like a single distributed system. The RCS can accept digital signals or include a thresholding option (T) that digitizes analog signals directly from a single photon detector with programmable threshold and phase.

Basic Features

Count detection events on up to four local and four remote detectors at 1.25 GHz sampling rates
Programmable delays and multiple clock domains to account for fiber delay
Four programmable outputs that are Boolean functions (AND, OR, XOR, NOT, any combinations thereof) of the detector outputs (1.25 GHz update); e.g. the raw detector binary output on the individual detectors or an indication of any particular correlation being detected
Optional DWDM optical link connects two CPDS-2000's; correlations
Large memory for storing raw data for off-line processing (~4 Terabits typical storage, can be synchronized to an electrical trigger or received signal from optical channel)

Product Specifications

Attribute	Value	Units	Comments
Number Electrical Inputs	4
Input Clock Frequency	50-1250	MHz	At the baud rate or an integer sub-multiple.
Sampling Rate	50-1250	MHz	Sample digital signal to look for transitions; can be at or faster than the optical pulse rate.
Programmable Correlation Delay	0-2^-19	Clock Cycles
Typical Data Storage	4	Terabits	Number of storable bits depends on the detection rate; for 10^-4 singles count rate the compression factor is 500:1. Raw memory is 8 Gbits leading to 4 Terabit of storable raw data.
OC Channel Sensitivity	~20	dBm	Tx power ~0 dBm. User-selectable DWDM SFP channel.
Clock Input	0.08 ... 1.25	Vpp
Phase Control	78.1	ps	Granularity of control of sampling phase.
Masking Length	0,4,7,15,23,31,39,47, 55,63,infinite (RZ)	sampling cycles	Number of samples ignored after a detection event ignored to mitigate after-pulsing.

Typical Applications

Measure entangled light distributed over different fiber lengths
Quantum key distribution (QKD)
Quantum feed-forward processing

Product Photo & Diagram