Introduction
The history of electromagnetic waves being used for communication is rather long. People have been receiving and sending signals since the end of the nineteenth century. The style of the antenna used for radio received has been the same for many years as well (Emerging Technology from the arXiv). However, with the rise of a new branch of physics, quantum computing enters new territories, aiming to reform one of the most common communication devices (Cooper). Known as Rydberg physics, this sphere of atomic research uses exited atoms to gather and transfer radio signals.
The innovation has been introduced recently and submitted to the scholarly archives in the summer of 2018. In their study, Anderson et al. show how “cesium Rydberg vapors” can be contained into a small cell and used to detect baseband signals, acting as a radio antenna. The researchers’ intent is to improve the structure of such antennas and, most importantly, to reduce or eliminate the risk of electromagnetic interference (EMI) (Anderson et al.).
While the currently presented device does not outperform regular antennas in their range of received frequencies, its potential can pave the way for a new type of communicational technology. The future application of an atomic radio communication receiver is yet to be appraised and tested, but the implications for atomic physics are astounding.
Predecessors and Previous Research
In order to understand the revolutionary idea of the atomic-based received, one has to discuss the design of antennas used at the present time. These devices usually come in the form of a long metal rod; received often need multiple antennas to gather information (Emerging Technology from the arXiv). When being exposed to radio waves, the electrons inside these rods accelerate. As a result, the energy of the wave is converted into an electrical current which is then amplified and delivered to the person listening to the radio.
These antennas are exposed to multiple issues which scientists hope to solve with the new technology. First of all, these rods take up space which is, which in some situations is not beneficial to the owner of a radio. Second, they do not capture a wide range of wavelengths. Finally, they are subject to EMI, which disrupts information transfer and makes radio communication unreliable and exposed to outside influence.
Rydberg physics is a growing research sphere that tries to resume these problems with the help of atoms. This branch of physics is closely connected to quantum computing, the science which employs particles in superposition as a way of energy transition (Cooper). Rydberg atoms have a single outer valence electron which is excited to increase the atomic radius. (Cooper). As a result, their interaction with other atoms is different; they create a dipole moment that is much more powerful than that between regular atoms (Cooper). Thus, such high interactivity presents the potential for designing fast and efficient information systems.
Main Idea
The connectivity or Rydberg atoms is used by Anderson et al., who utilize excited atoms of cesium. Their idea is that the vapors of cesium Rydberg atoms are extremely sensitive to any small electric field. The frequencies at which such atoms resonate are identical to those that are used for communication over radio and microwave signals (Jarman). Therefore, encasing these atoms in a container and making them interact with radio wave signals can result in a better version of a receiver.
Another interesting detail is the fact that such systems will not require a demodulator. In regular antennas, this electric circuit is a vital part of the device since it extracts the signal with information from the wave. In the introduced atom-based systems, the signal is not modulated in the first place; the Rydberg atoms respond to FM and AM signals directly (Jarman). As a result, the new antennas do not require excessive circuitry and can be made in a very compact size.
Setup
As it is mentioned above, the Rydberg atoms are put in a cell in the form of vapor. Anderson et al. use cesium gas as the basis for their experiments due to their field sensitivity. The centimeter-sized cell is made from glass; it is attached to a quantum-optical readout, a laser adjusted to a specific frequency (Emerging Technology from the arXiv). This laser is used to detect the received radio baseband signals since it can make the gas of Rydberg atoms transparent in certain conditions.
The explanation states that one laser is directed at the gas to saturate its light absorption, and another beam passes through this gas to calculate its transparency (Emerging Technology from the arXiv). This measure fluctuates when atoms interact with radio waves – this is the central part of the process that happened in the antenna. The information about the frequency and amplitude is then displayed with the help of a photodiode. The scheme of this process demonstrates the simplicity of the concept (see fig. 1). The atomics radio, therefore, is much smaller than the currently used system. It consists of a small glass cell with gas and a couple of lasers.
Uses
It is clear that the primary intended purpose of this new device is to function as a radio communication receiver. According to the findings of Anderson et al., such atomic radios function similarly to the regular antennas and receivers. They can modulate frequencies that range over four octaves (starting with C-band and ending with Q-band). This is the range of human hearing – thus, such glass vapor cells may replace radios in some years. An atom-based receiver picks up AM and FM microwave signals without any complications; its bandwidth is 3-dB, and its baseband is around 100kHz (Anderson et al.). However, the use of such receivers should not be restricted to serving as a radio replacement.
Benefits and Drawbacks
The introduction of a new concept in the field of radio technology can be substantial, but it is crucial to analyze the advantages and disadvantages of this system prior to establishing its superiority. For example, it is apparent that the new atom-based receiver is much more compact than a regular antenna-utilizing device (Anderson et al.). It is a benefit for locations where antennas cannot or should not be placed. Electronics are becoming smaller with the advancement of technology, but the design of antennas has been virtually the same for many decades. This new idea completely changes the way one perceives information transfer.
Another useful feature of an atomic radio is its ability to work without demodulation. Apart from saving even more space, the new structure simplifies the activities needed to transfer data. Furthermore, this aspect is significant since the radio’s signal does not lose its quality without a demodulator. According to Jarman, the scientists were able to record a song, “Mary Had a Little Lamb,” using their prototype without any issues. This experiment also allowed scientists to test the range of recognized octaves. The results, in this case, are positive as well because the new radio can record almost all octaves that humans can hear.
The final discovered benefit is the new receiver’s protection from EMI. Atom-based systems are thought to be more resilient to interference which is often remarked as one of the major problems in radio communication (Anderson et al.). In fact, some of the EMI-related problems may render usual antennas completely useless, but no devices were available to replace such unstable systems to this day. The implementation of the new technology could be an important step in protecting information and improving the quality of transfers (Emerging Technology from the arXiv). The need to condition the signal or place antennas in certain places may cease to exist with the introduction and spread of atomic radios.
Nonetheless, at the current stage of research, atom-based receivers have some weaknesses. Modern devices have a certain standard for the dynamic range that a receiver should possess. Anatomic radio did not achieve those rates, although its results were not significantly worse than those of regular equipment (Jarman). This is the only known drawback since not much information about the experiments exists. The scientists’ focus on reaching and exceeding these standards is one of the next goals in developing the technology.
Implications for Future Research
The field of quantum computing presents many opportunities for scientists to further their investigations. As their next goal is to perfect the system and make its dynamic range wider, they may start thinking about introducing the new technology into industries where information quality and safety are crucial in radio communication. Moreover, this finding suggests that alternatives to the commonly used antennas exist. Such a shift in scientific research can also impact other areas of development, including wireless technology and the internet (Wi-Fi). However, in order to apply the accumulated knowledge in other areas, the researchers should test their project more and find ways to enhance its performance.
Conclusion
Atom-based receivers for radio communication use Rydberg atoms of cesium vapors as the basis for collecting information. The scientists excite the gas’ atoms to increase their sensitivity to electromagnetic signals. As a result, they function similarly to antennas, recording data in real-time. However, these devices have many advantages which regular antennas do not have. They are much more compact, taking up a centimeter-sized glass box.
They also do not need a demodulator since their processes result in the direct transfer of signals. Finally, they are almost completely protected from EMI – their resistance to interference can keep the information undisturbed. The quality of the transmission and its range is adequate, although they may require some adjustments. However, the revolutionary design of such radios can be seen as a significant step in reforming the current technologies. The idea of atomic receivers replacing the current antenna-based devices is not impossible. Their simple design and a straightforward process of receiving information can bring many changes to the scientific world and quantum computing in the following years.
Works Cited
Anderson, David A., et al. “An Atomic Received for AM and FM Radio Communication.” arXiv. Web.
Cooper, Keith. “The Rise of Rydberg Physics.” Physics World. 2016. Web.
Emerging Technology from the arXiv. “Get Ready for Atomic Radio.” MIT Technology Review. 2018. Web.
Jarman, Sam. “Radio Uses Rydberg Atoms to Play ‘Mary Had a Little Lamb.’” Physics World. 2018. Web.