A team of experimentalists working with cold Rydberg atoms have used Quantum magnetometry to help the atomic clocks and magnetometers used for precise time keeping in navigation, telecommunication and aviation, achieve higher precision and make them additionally robust.
A Rydberg atom is an excited atom with one or more electrons that have a very high principal quantum number. This state of excitation is measured with a spectroscopic method called the Electromagnetically Induced Transparency (EIT).
Researchers at the Raman Research Institute (RRI) have leveraged the Doppler effect to their advantage and achieved a ten times enhanced response to the magnetic field while performing quantum magnetometry (phenomenon exploiting the quantum nature of light and atoms for precision measurement of magnetic fields) on thermal rubidium atoms using Rydberg Electromagnetically Induced Transparency (EIT) in a room temperature-based environment.
Electromagnetically Induced Transparency (EIT) is a fascinating phenomenon which makes an opaque medium transparent, can slow down light pulses to crawling speeds and even trap light inside atomic media. EIT has led to a myriad important applications in precise atomic clocks, atomic magnetometers and quantum computation. EIT generally occurs in a three-level atomic system involving two atomic transitions addressed by a weak probe laser beam and a strong coupling laser beam.
Scientifically, interference occurs when a wave is able to travel between two points via multiple paths, either resulting in their enhancement or cancellation. On similar lines, an atom can transition between multiple quantized energy levels by different routes that can interfere. This determines the amount of light an atom absorbs.
Similar to interference of light, where constructive interference gives bright fringes and destructive interference gives dark fringes, the probabilities of atomic transitions between these energy levels can also interfere destructively, known as quantum interference. It can result in atoms in a dark state to not absorb the probe light and thereby render the atomic medium transparent. This phenomenon is called Electromagnetically Induced Transparency (EIT).
