Measuring the passage of time in our world of ticking clocks and oscillating pendulums seems straightforward – just count the seconds between ‘then’ and ‘now’.
However, at the quantum level of buzzing electrons, predicting ‘then’ is not always possible, and ‘now’ often dissolves into vagueness. In such scenarios, a stopwatch won’t suffice.
An innovative approach to this timekeeping challenge was proposed in a 2022 study by researchers from Uppsala University in Sweden, focusing on the wave-like behavior of Rydberg states.
Rydberg atoms, inflated with lasers rather than air, house electrons in high-energy states far from the nucleus.
Employing lasers to elevate electrons to higher energy states is a common practice, with the ‘pump-probe’ technique utilizing a second laser to track electron movements and time progression, especially in ultrafast electronics.
Manipulating atoms into Rydberg states proves valuable in developing components for quantum computers, unveiling insights into electron behavior in such states.
Rydberg wave packets, the mathematical rules governing electron movement, create distinctive interference patterns when multiple packets coexist, each marking a unique timespan.
Researchers successfully demonstrated that these patterns could function as quantum timestamps, being consistent and reliable markers of temporal duration.
This novel method eliminates the need for a precise starting point, offering a unique approach to time measurement, akin to determining the race time of an unknown sprinter against competitors of known speeds.
By employing evolving Rydberg wave packets in combination with pump-probe spectroscopy, scientists can timestamp events lasting mere trillionths of a second, with the potential to expand this technique for varied conditions using different atoms or laser energies in future experiments.
This groundbreaking research was featured in Physical Review Research, showcasing the innovative strides in quantum time measurement.
An adjusted version of this piece was previously published in October 2022.
Vocabulary List:
- Rydberg /ˈrɪd.bɜːrɡ/ (adjective): Referring to atoms with one or more electrons in high-energy states far from the nucleus.
- Oscillating /ˈɒs.ɪ.leɪ.tɪŋ/ (verb): Moving or swinging back and forth in a regular rhythm.
- Interference /ˌɪn.təˈfɪə.rəns/ (noun): The combination of two or more waveforms to form a resultant wave.
- Spectroscopy /spɛkˈtrɒs.kə.pi/ (noun): The study of the interaction between matter and electromagnetic radiation.
- Timestamp /ˈtaɪm.stæmp/ (noun): A record of the time at which an event occurs.
- Innovative /ˈɪn.ə.və.tɪv/ (adjective): Introducing or using new ideas or methods.
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