Related papers: Information transfer by quantum matterwave modulat…

Recently, we have shown theoretically [1] as well as experimentally [2] how the phase of an electromagnetic field can be determined by measuring the population of either of the two states of a two-level atomic system excited by this field,…

State discrimination is a key challenge in the implementation of quantum communication protocols. Most optical communication protocols rely on either coherent states of light or fragile single-photon states, making it often difficult to…

Wave--particle duality demonstrates the peculiar nature of quantum mechanics. In which-way experiments, depending on the measurement scheme, a particle exhibits either wave-like or particle-like properties, as summarized by Bohr's principle…

High contrast matter-wave interferometry is essential in various fundamental quantum mechanical experiments as well as for technical applications. Thereby, contrast and sensitivity are typically reduced by decoherence and dephasing effects.…

We suggest a method to perform a quantum logic gate between distant qubits by off-resonant field-atom dispersive interactions. The scheme we present is shown to work ideally even in the presence of errors in the photon channels used for…

In quantum information processing, quantum cavities play an important role by providing the mechanisms to transfer information between atom qubits and photon qubits, or to couple single atoms with the optical modes of the cavity field. We…

We propose a method for spatially re-routing single photons or light in a coherent state with small average photon number by purely electronic means, i.e. without using mechanical devices such as micro-mirror arrays. The method is based on…

We devise a new technique to enhance transmission of quantum information through linear optical quantum information processors. The idea is based on applying the Quantum Zeno effect to the process of photon absorption. By frequently…

Certain quantum devices, such as half-wave plates and quarter-wave plates in quantum optics, are bidirectional, meaning that the roles of their input and output ports can be exchanged. Bidirectional devices can be used in a forward mode and…

Forthcoming quantum devices will require high-fidelity information transfer across a many-body system. We formulate the criterion for lossless signal propagation and show that a single qubit can play the role of an antenna, collecting large…

The frequency conversion of light has proved to be a crucial technology for communication, spectroscopy, imaging, and signal processing. In the quantum regime, it also offers great potential for realizing quantum networks incorporating…

Communication over proven-secure quantum channels is potentially one of the most wide-ranging applications of currently developed quantum technologies. It is generally envisioned that in future quantum networks, separated nodes containing…

Energy transfer and information transmission are two fundamental aspects of nature. They are seemingly unrelated, while recent findings suggest that a deep connection between them is to be discovered. This amounts to asking: Can we phrase…

Photons are natural carriers of quantum information due to their ease of distribution and long lifetime. This thesis concerns various related aspects of quantum information processing with single photons. Firstly, we demonstrate N-photon…

Based on principle of quantum mechanics, quantum cryptography provides an intriguing way to establish secret keys between remote parties, generally relying on actual transmission of signal particles. Surprisingly, an even more striking…

Processing and distributing quantum information using photons through fibre-optic or free-space links is essential for building future quantum networks. The scalability needed for such networks can be achieved by employing photonic quantum…

Converting low-frequency electrical signals into much higher frequency optical signals has enabled modern communications networks to leverage both the strengths of microfabricated electrical circuits and optical fiber transmission, allowing…

Fast, efficient, and low power modulation of light at microwave frequencies is crucial for chip-scale classical and quantum processing as well as for long-range networks of superconducting quantum processors. A successful approach to bridge…

We present a quantum secure direct communication protocol where the channels are not maximally entangled states. The communication parties utilize decoy photons to check eavesdropping. After ensuring the security of the quantum channel, the…

The classical theories of communication rely on the assumption that there has to be a flow of particles from Bob to Alice in order for him to send a message to her. We develop a quantum protocol that allows Alice to perceive Bob's message…