Quantum Entanglement and its Applications

For those who struggled through a physics class or never studied it in the first place, Quantum Entanglement may seem completely foreign; however, the basics are not too hard to understand.  We will explain these basics and then introduce you to some current and future applications.

The Quantum Entanglement Basics

Newtonian physics works till a point, then another set of rules like, Einstein’s relativity and even deeper Quantum Mechanics take over.  This can be thought of like a pile, the grains of sand that make up that pile, and the silicon atoms that make up the sand; they are the same thing and different.

Quantum Entanglement is a state where two systems (a system is usually an electron or photon) are so strongly correlated that the obtaining of information about one system’s “state” (the direction of the electron’s spin say “Up”) will give immediate information about the other system’s “state” (the second electron’s spin is in the opposite direction “Down” 100% of the time) no matter how far apart these systems are.  The “immediate” and “no matter how far apart they are” is a big deal.  This phenomenon had baffled scientists like Einstein because the state is not determined until it is measured and the transmission of information violates the traditional physics’ rule, which says that information cannot be transferred faster than the speed of light.  However, research and testing starting in the 1980s have validated entanglement using both photons and electrons.

Two subatomic particles (the electrons) can be prepared in a way that can describe them with a single wave function.  One way that entanglement can be accomplished by letting a parent particle, with zero spin, decay into the two entangled daughter particles with equal but opposite spin.

If the two daughter particles don’t interact with anything, they will keep their wave function (when measured) equal and opposite no matter how far apart they are.  Through testing, scientists have found that the information is not determined from the time of entanglement. Instead, only when one measures the information of one particle is that information then transmitted to the other particle, and this is faster than the speed of light.  So the information does move this quickly, but we cannot control it; this lack of control does limit the potential uses for Quantum Entanglement, such as sending a message or other info faster than light speed (or does it?).

So How Can Quantum Entanglement Be Used?

Several applications can take advantage of this unique physical property that will change our present and future.  Entanglement can enable quantum cryptography, superdense coding, maybe faster than light speed communication, and even teleportation.

Because of its potential, multiple industries, including finance and banking, hope to solve time and processing power-consuming problems with quantum computers.  Quantum entanglement is a phenomenon that can potentially aid such computers, cutting down on time and computing power needed to process information transfer between their qubits.

Quantum Cryptography

In traditional cryptography, the sender uses one key to encode, and the recipient uses the shared key to decode the message.  However, this process suffers from the risk of a third-party learning information about the keys and being able to intercept and compromise the cryptography.

Creating a secure channel is the key to unbreakable cryptography between two parties.  Entanglement can create this.  Two entangled systems mean that they are correlated with each other (when one changes, so does the other), and no third party will share this correlation.  Quantum cryptography also benefits from no-cloning, meaning that it is impossible to create an identical copy of an unknown quantum state.  Therefore, it is impossible to copy data encoded in a quantum state.  Quantum Cryptography has already been accomplished with an unbreakable quantum key distribution (QKD).  QKD, sends information about the key using randomly polarized photonsThe recipient uses polarized filters to decipher the key with a chosen algorithm used to encrypt the message.  The secret data still gets sent over normal communication channels but can only decode the message with the exact quantum key.  Security is enhanced because “reading” the polarized photons changes their states, and any eavesdropping will alert the communicators of the breach.

Image courtesy of Quantum Flagship Europe

QKD technology is currently limited by fiber optic cable, which can send a photon about 100km before becoming too dim to receive.  The first entangled QKD bank transfer was made in Austria in 2004.  Ensuring transfer of unbreakable and tamper-proof communications that is provably secure based on the laws of physics has obvious use in finance, banking, military, medical, and other services.  Several companies are using entangled QKD now.

Improved Microscopy

A team of Japanese researchers at Hokkaido University developed the world’s first entanglement-enhanced microscope. This microscope fires two beams of photons at a sample and measures the interference created by the reflected beams.  The Entangled photons increased the amount of information gathered and thus the sharpness.  Besides the advances possible with telescopes, several other scientific fields gain from increased sensitivity of instruments, including nanotechnology.

Quantum Teleportation

Not what we that love Sci-Fi think of, but Quantum teleportation is the exchange of quantum information, photons, atoms, electrons, and superconducting circuits, between two parties.  Teleportation allows Quantum Computers to work in parallel, dropping power consumption up to 100 to 1000 times.  Quantum teleportation exchanges “quantum” data over a classical channel differing from Quantum Cryptography, which exchanges “classical” data over a quantum channel.  The power requirements of quantum computers produce heat which is an issue when they also require such low temperatures to function.  Teleportation can lead to design solutions that will bring the development of quantum computing faster.

Superdense Coding

Superdense coding is the transportation of two classical bits of information using one entangled qubit.  This means that a user can:

  • Send half of what will be needed to reconstruct a classical message ahead of time, allowing the user to transmit at double speed until the pre-delivered qubits are exhausted.
  • High-latency bandwidth can be converted to low latency bandwidth, sending half of the information over the high latency channel supporting the data coming over the low latency channel.
  • Double the capacity in one direction of a two-way quantum channel

Every generation of communication has required more data transmission.  Superdense coding will allow a similar increase in information.

Biological Systems

Like all organisms, the human body constantly changes with thousands of chemical and biological processes interacting.  Until recently, these were thought to be linear, “A” leading to “B”.  However, quantum biology and biophysics have discovered a tremendous degree of coherence within living systems, and QE potentially playing a role. It is possible that the way in which the different subunits forming protein structures are packed together may have evolved to enable sustained quantum entanglement and coherence.  Quantum Biology is still a theoretical field with several questions requiring further experimentation; as these are answered, applications in medicine will become more apparent.  Quantum computing can ideally mimic nature (modeling atomic bonding) and quantum biological systems better than traditional computers.

Maybe Information Can Be Transmitted After All

An international team of physicists has published a study in Physical Review X, demonstrating quantum entanglement can be strengthened, overcoming very high levels of noise, which happen in applications outside the laboratory. This strengthening is accomplished by not using the traditional quantum qubits and instead employ entanglement of systems with more than two levels.  This has allowed observation of quantum entanglement under harsh environmental conditions.  The experiment proves implementation and could be ready for long-distance quantum communication under real-world conditions.  This new method may prove helpful for distributing entanglement in a future quantum internet.


Quantum Entanglement may provide us new ways to work with data that were once thought impossible.  With the future of Quantum Computing, we will attempt to answer questions that required so much data we could never have processed before and combining it with QE; we can do that in more efficient and secure ways.  Adding in the biological and astronomical applications, QE may be used to solve those questions humans have always pondered; where did we really come from, and how did it all begin?  As the technology develops, the more uses we will find for it, amazing potential for sure.


Disclaimer:  The author of this text, Jean Chalopin, is a global business leader with a background encompassing banking, biotech, and entertainment.  Mr. Chalopin is Chairman of Deltec International Group,

The co-author of this text, Robin Trehan, has a Bachelor’s degree in Economics, a Master’s in International Business and Finance, and an MBA in Electronic Business.  Mr. Trehan is a Senior VP at Deltec International Group,

The views, thoughts, and opinions expressed in this text are solely the views of the authors, and do not necessarily reflect those of Deltec International Group, its subsidiaries, and/or its employees.