Chapter 2 Description; Temperature Range - THORLABS SPDC810N User Manual

Narrowband Photon Pair Source
Chapter 2 Description
Introduction
Thorlabs' SPDC810N is a collinear type‐II Spontaneous Parametric Down‐Conversion (SPDC) source. Inside, a
nonlinear crystal converts individual 405 nm photons into pairs of orthogonally polarized 810 nm photons in a
single event. These pairs are split by polarization into two channels and delivered to the two polarization
maintaining (PM) fiber outputs.
The 405 nm photons are produced by an integrated diode laser with an adjustable power of up to 40 mW. The
efficiency of the down‐conversion process is approximately 10
femtowatts.
Wavelength degeneracy of the output photons can be tuned via crystal temperature adjustment, done through
an adjustment knob on the front panel.
The display screen shows the pump level and device status, which includes the crystal temperature and emission.
An indicator light is also included on the enable button to show when the internal laser is active.
For added safety, there is an interlock connector located on the rear panel that must be shorted in order for the
output to be enabled. This can easily be configured to be triggered by doors to disable the unit in unsafe
conditions. An enable button must be set to activate the unit, and a green LED indicator displays the current state
of the unit. There is a 3 second delay before the pump laser turns on, and the user is warned by the rapidly blinking
LED.
The SPDC810N include a universal power supply allowing operation over 100 to 240 VAC without the need for
selecting the line voltage. The fuse access is conveniently located on the rear panel.
Shipping List
The SPDC810N consists of the following components:

Benchtop, Narrowband Photon‐Pair Source

Interlock‐Shorting BNC Connector

Region‐Specific Power Cord

USB Type A to Type B Cable, 6.56' Long

Two P1‐780PMAR‐2 AR Coated Patch Cables

FBC250 Fiber Connector and Bulkhead Cleaner

FCC‐7020 Fiber Connector Cleaner
Operating Conditions and Environmental Requirements
In order to achieve optimal performance of the laser system, please observe the following guidelines.
2.3.1 Temperature Range
Control of the ambient room temperature is important for stable operation of the system. The lab temperature
should be in the range of 18 °C ‐ 25 °C.
If unpacking the device for the first time and it is extremely cold (from shipping conditions, for instance), allow it
to come to room temperature before opening the sealed internal bag. This will prevent condensation on internal
optics and damage or permanent reduction in performance.
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, leading to an output power on the order of
Chapter 2: Description
TTN271994‐D02