A New Quantum Technique Could Change How We Study the Universe

A New Quantum Technique Could Change How We Study the Universe ...

In astronomy, there is a broad set of developments. In the last ten years, exoplanet studies have expanded dramatically, gravitational wave astronomy has emerged as a new field, and the first images of supermassive black holes (SMBHs) have been discovered.

A related field, interferometry, has also developed incredibly grace to highly-sensitive instruments and the ability to share and combine data from observatories worldwide. In particular, the science ofvery-long baseline interferometry(VLBI) is bringing new realms of possibility.

According to a recent survey from Australian and Singapore, a fresh quantum technique may boost optical VLBI. It''s known asStimulated Raman Adiabatic Passage (STIRAP), which allows quantum information to be transferred without losses.

This technique, once integrated with next-generation instruments, may allow for more detailed black holes, exoplanets, the Solar System, and the surfaces of distant stars.

Zixin Huang, a postdoctoral researcher at the Macquarie University in Sydney, Australia, led the research. Gavin Brennan, a theoretical physics professor at the Department of Electrical and Computer Engineering and the Centre of Quantum Technologies at theNational University of Singapore(NUS), and Yingkai Ouyang, a senior research fellow at the Centre of Quantum Technologies at the University of Queensland.

To put it bluntly, theinterferometrytechnique involves combining light from various telescopes to create images of an object that would otherwise be too difficult to resolve.

The very-long baseline interferometry refers to a specific technique used in radio astronomy where signals (black holes, quasars, pulsars, star-forming nebulae, etc.) are combined to create detailed images of their structure and activity.

VLBI has produced the most detailed representations of the stars orbiting Sagitarrius A*(Sgr A*) and the SMBH in our galaxy. It also allowed astronomers with theEvent Horizon Telescope(EHT) collaboration to capture the first image of a black hole(M87*) andSgr A*itself!

However, as they said in their study, classical interferometry is still hampered by several physical limitations, including information loss, noise, and the fact that the light obtained is generally quantum in nature (where photons are entangled). VLBI may be used for far more fine astronomical surveys.

According to Dr. Huang, "Although the majority of our standard baseline imaging systems operate in the electromagnetic spectrum, it''s very difficult to do over large distances: noise sources can come from the instrument itself, thermal expansion and contraction, vibration and etc.; and on top of that, optical elements can be lost.

"This approach of research is to allow us to enter the optical frequencies from microwaves, but these techniques are equally applicable to infrared. However, this task in optical frequencies becomes extremely difficult, even the fastest electronics cannot directly measure the oscillations of the electric field at these frequencies."

According to Dr. Huang and her colleagues, quantum communication techniques such as the Stimulated Raman Adiabatic Passage are the key to successfully overcoming these limitations. STIRAP involves transferring optical information between two applicable quantum states.

Huang claims that when applied to VLBI, it will allow for efficient and selective population transfers between quantum states without suffering from normal problems of noise or loss.

The process they envision would involve coherently coupling the starlight into "dark" atomic states that do not radiate, as they describe in their paper.

Huang says the next step is to combine the light with quantum error correction (QEC), a technique used in quantum computing in order to protect quantum information from accidental defects due to decoherence and other "quantum noise."

According to Huang, this same technique might provide greater depth and exact interferometry:

"For example, the light must be collected and processed in tandem with a large optical interferometer, and we propose to use quantum error correction to mitigate errors due to loss and noise in this process.

"Quantum error correction is a rapidly expanding area primarily geared towards enabling scalable quantum computing in the event of errors. In combination with pre-distributed entanglement, we can perform the tasks that can extract the information we need from starlight while suppressing noise."

The team analyzed a scenario in which two facilities (Alice and Bob) are separated by long distances to collect astronomical light to test their theory.

Each share a pre-distributed entanglement and contains "quantum memories" into which the light is captured, and each creates its own set of quantum data (qubits) into some QEC code. By a decoder, the data is then infected with other high-end noise situations.

Through the STIRAP technique, the signal in the quantum memories is captured in the "encoder" phase, which allows the incoming light to be coherently coupled into a non-radiative state of an atom.

In addition, the ability to capture light from astronomical sources that account for quantum states (and eliminate quantum noise and information loss) would be a game changer for interferometry. These improvements would have significant implications for other areas of astronomy that are also being radicalized today.

"Prin converting into optical frequencies, such a quantum imaging network will increase imaging resolution by three to five orders of magnitude," says Huang.

"It would be powerful enough to see small planets around nearby stars, details of solar systems, kinematics of stellar surfaces, accretion disks, and potential info around the event horizons of black holes none of which currently planned projects can resolve."

TheJames Webb Space Telescope (JWST) will utilize its advanced collection of infrared imaging techniques to characterize exoplanet atmospheres like never before. The same applies to ground-based observatories like theExtremely Large Telescope(ELT),Giant Magellan Telescope(GMT) andThirty Meter Telescope (TMT).

These observatories will allow for direct imaging of exoplanets, revealing valuable information about their surfaces and atmospheres.

Observories will have a different way to capture photographs of some of the most unaccessible and difficult-to-see objects in our Universe, thanks to new quantum techniques. This is a must-see secret that will be certain to be (last time, I promise!) revolutionary!

This article was first published by Universe Today. Read the original article.

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