Amplify Your Precision for Small Samples and Minor Isotopes

Experience more than 5 times better precision for small samples using our new amplifier technology

Thermo Fisher Scientific has developed a new design of amplifiers equipped with 1013 ohm resistors. The revolutionary new resistor design guarantees fast response times and extremely low noise characteristics. These new amplifiers are available for our TIMS, MC-ICPMS, Gas IRMS and Noble Gas Mass Spectrometers.

The new 1013 ohm amplifiers open the door to more applications that up-to-now have not been explored as of the limited detection technology. With a factor of 4-5 better precision compared to the 1011 ohm current amplifiers, we can now analyze sample sizes that have not been possible to analyze before. Especially samples with expected large isotope variations, like melt inclusions, extraterrestrial material, dust inclusions in ice cores and nuclear safeguards. Here variations can be severe, but material is usually very scarce. Ultimately, the precision and accuracy of such material analyses are limited by the signal/noise ratio, the calibration of the detection system and the analytical blanks. As of the large variations, the required precision is typically in the tens to couple of hundreds of ppm, ideally suited for 1013 ohm amplifiers.

The precision of analyses of small ion beams in multi-collection mass spectrometry is fundamentally limited by:
1. the error introduced by counting statistics, and
2. the electrical Johnson-Nyquist noise of the resistor used in the multiplier’s feedback loop
From the Johnson-Nyquist noise equation, it follows that if the resistor value (and thus the output V) is increased by a factor of 100, as is the case when a 1013 ohm amplifier is used, the noise will only increase by √100. Compared to a default 1011 ohm amp, the signal to noise ratio can be expected to improve by a factor of 10. In practice, we achieve a 4-5 times improvement in signal to noise.

Key Benefits

  • New Low Noise Amplifier Technology
  • Highest Dynamic Range in Class
  • Lowest Signal/Noise on Faraday Cups
  • Fast Response Time