Compact Q-Band EPR Spectrometer

Pulsed dipolar EPR spectroscopy is a powerful tool to measure highly accurate distances between dipolar coupled electron spins (pairs of nitroxide spin labels, metals centers, etc.). When using nitroxide spin labels this technique is most sensitive at Q-Band frequencies (34 GHz).
Small Footprint

Small Footprint

The Bridge12 Q-Band system is a compact spectrometer that will fit easily in any laboratory. The system is based on a compact, liquid cryogen-free superconducting magnet with an integrated liquid cryogen-free variable temperature insert. In its default configuration the magnet reaches a magnetic field of up 1.5 T (option for 3.5 T available) and the cryostat can reach a base probe well below 2.4 K. Being a dry system, the spectrometer can run 24/7 without worrying about when the liquid helium runs out for cooling.

The magnet has a very small, compact footprint and with a weight of just above 140 kg the magnet can be placed almost anywhere, even in a crowded lab environment.

High-Power AWG Pulses

High-Power AWG Pulses

Microwave pulses are created by the Bridge12 X-IF bridge and upconverted to Q-Band frequencies using a frequency extension. The spectrometer is controlled by SpecMan4EPR. A powerful feature of SpecMan4EPR is its AWG engine. It easily allows even beginners to create the most sophisticated microwave pulse shapes. SpecMan4EPR supports digital downconversion filtering of the EPR spectral data.

The spectrometer comes with a 100 W solid-state Amplifier (optional 40 W). The circulator attachment can be easily detached to allow connecting EPR probes with a cryogenic pre-amplifier.

Bridge12 Q-Band LGR

Bridge12 Q-Band LGR

The spectrometer comes with the Bridge12 Q-Band loop-gap resonator (B12TQLP-1.6), a probe head optimized for pulsed dipolar EPR spectroscopy (e.g. DEER/PELDOR, SIFTER, RIDME, DQC, etc) in cases where the sample amount is limited. The resonator can be operated from 2 K to room-temperature and is compatible with all standard EPR cryostats. The loaded Q of the resonator is < 85 (> 400 MHz bandwidth), with a B1e of > 6 G/√W.

The Bridge12 Q-Band spectrometer was developed under a Small Business Innovation Research (SBIR) Grant by the National Institute of General Medical Sciencies (NIGMS) of the National Institutes of Health (NIH).

Technical Specifications

  • Spectrometer Frequency: 34 GHz (typ.)
  • Maximum pulse power: 100 W (40 W option available)
  • Maximum duty cycle: 5 %
  • AWG bandwidth: 400 MHz (higher bandwidths available)
  • AWG resolution: 14 bit
  • Digitizer sample rate 1.25 GS/s
  • Digitizer resolution: 8 bit
  • Magnet field range: 0 - 1.5 T
  • Field homogeneity: < 25 ppm (10 mm DSV)
  • Magnet weight: 140 kg
  • Field resolution: 20 bit
  • VTI temperature range: 2 - 325 K
  • Cold bore diameter: 40 mm

Any questions?