Rosatom Announces Breakthrough: Russia Builds a Source of Quantum Squeezed Light

Russian scientists have developed a source of quantum "squeezed" light, a technology that, according to Rosatom, only a few countries in the world possess. The new development opens prospects for progress in several key areas of quantum technology.

What is quantum "squeezed" light?

In quantum optics, "squeezed" light (squeezed light) refers to a special state of the light field in which the quantum noise of one measurable quantity, such as amplitude, is suppressed below the so-called standard quantum limit. This is possible thanks to Heisenberg's uncertainty principle: by reducing noise in one variable, one inevitably increases it in the conjugate variable (here, the phase). No laws of physics are violated; it is merely a controlled redistribution of quantum uncertainty.

Building such sources is a non-trivial task. It requires special nonlinear optical media (crystals or fiber structures), highly stable laser systems and strict control over experimental parameters. That is why only the leading scientific powers have full-fledged squeezed-light technology.

Where is "squeezed" light used?

"Squeezed" light is one of the fundamental resources for several quantum disciplines at once:

• Photonic quantum computers: special states of squeezed light are used as qubits or as a resource for quantum error correction in optical circuits
• Quantum cryptography (QKD): allows communication channels in which an interception attempt is physically detectable
• Quantum metrology: measurements of frequency, length and time with precision beyond classical limits
• Quantum sensors: precision gravitational-wave detectors, and next-generation magnetometers and gravimeters

This explains why Rosatom described the development as a breakthrough in several areas at once: it is not about a specific device but about a base technology with a wide range of applications.

Context: Russia's quantum program

Russia is carrying out a state roadmap for quantum technologies, in which Rosatom is one of the key contractors for quantum computing. Mastering a squeezed-light source removes dependence on foreign supplies of quantum-optical equipment, a critically important element under the current technological restrictions.

The "club" of states that actually have squeezed-light sources and use them in scientific and applied work includes only a few countries: the US, Japan, China and a number of European states. According to Rosatom, Russia now belongs to that group.

What this means

The Russian scientists' achievement is not an isolated result but a strategic competence. Photonic quantum computing is gaining momentum in the global technology race precisely because photonic circuits do not require deep cryogenic cooling, unlike superconducting processors. By mastering the basic component of this field, Russia expands its own quantum roadmap and reduces import dependence in a strategically sensitive area.