Quantum Holograms Enable Disappearing Messages

Quantum holograms allow for the transmission of messages that can vanish selectively. This feature is achieved through entangled particles of light, enabling the erasure of holographic images. Secure communication can thus remain hidden, making it beneficial for privacy.

The method creates a quantum disappearing act, where secure messages are embedded into holograms. reports News Scientist. Parts of these holograms can be erased even after transmission. Quantum light signals are ideal carriers of information. Intercepting their messages destroys the sensitive quantum states that encode them.

Researchers, led by Jensen Li at the University of Exeter in the UK, designed quantum holograms using a metasurface. This 2D material possesses engineered properties enhancing its capabilities. Holograms contain complex information recoverable upon illumination. For example, a 2D holographic card projects 3D images with proper light angles.

To craft a quantum hologram, the team first emitted two entangled photons from a special crystal using a laser. These photons traveled along different paths, with only one interacting with the metasurface. Thousands of minute components altered the photon’s quantum state in a pre-arranged manner, encoding a holographic image.

The paired photon then went through a polarized filter. This filter designated which sections of the hologram would be visible and which would vanish. The first photon experienced a superposition of holograms, holding various possible variations of a message. Due to their entanglement, altering the second photon changed the first's resultant image upon reaching a camera.

In a test, the hologram included the letters H, D, V, and A. Applying a horizontal polarizing filter erased the letter H from the final output. Li posits that the metasurface could encode intricacies into photons, serving tools like quantum cryptography protocols efficiently.

Li presented his findings at the SPIE Optics + Photonics conference in San Diego, California, on 21 August. Andrew Forbes from the University of the Witwatersrand in South Africa noted the development's potential. Ultimately, compact quantum technology could align with existing devices like smartphones. The novel quantum holograms may also find applications in imaging minute biological structures within the burgeoning field of medicine.

Earlier, SSP reported that a worlds fastest microscope captures electron motion.