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Researchers at the U. S. National Institute of Standards and Technology and Carnegie Mellon University have developed a 2D graphene film that is capable of measuring quantized resistance on a computer chip. This film requires significantly less operating cost compared to the current standard, gallium arsenide.

Measuring quantized electrical resistance is based upon the integral quantum Hall effect, which states that when 2D semiconductor is at very low temperatures, and under a strong magnetic field, the resistance of the semiconductor becomes quantized. Current gallium arsenide devices require at most, 1.2 Kelvin (-272 Celsius or -457.5 Fahrenheit) and a magnetic field stronger than 5 Tesla. These conditions require extensive setup and are extremely expensive to run. The 2D graphene film is able to measure the same quantized resistance, but allows for temperatures up to 5 Kelvin (-268.2 Celsius or -450.7 Fahrenheit) and a magnetic field of 2 Tesla. While this may not seem like a profound change in temperature, 1.2 Kelvin requires using liquid helium while 5 Kelvin requires only a closed cycle refrigerator.

The other useful benefit of the 2D graphene film is it can measure much higher currents than a gallium arsenide film. Gallium arsenide films can only support current up to 80 microamperes, while the graphene film was able to support current up to 720 microamperes. These higher currents allow accurate calibration of higher resistance devices, up to 10,000 ohms.

The U.S. National Institute of Standards and Technology is hoping to change the national standard of measuring quantized resistance from gallium arsenide to graphene within the next two years. Testing costs of quantized resistance will likely fall once graphene film based devices are commercially available. Regardless of which standards are applicable to your product, let Product Safety Consulting be "Your Outsourced Compliance Department".