Publications (12)
Phase Estimation of Coherent States with a Noiseless Linear Amplifier
Syed Assad, Mark Bradshaw, Ping Koy Lam
Amplification of quantum states is inevitably accompanied with the introduction of noise at the output. For protocols that are probabilistic with heralded success, noiseless linear…
Thermodynamic resources in continuous-variable quantum systems
Varun Narasimhachar, Syed Assad, Felix C. Binder +3
Thermodynamic resources, beyond their well-known usefulness in work extraction and other thermodynamic tasks, are often important also in tasks that are not evidently thermodynamic…
12.6 dB squeezed light at 1550 nm from a bow-tie cavity for long-term high duty cycle operation
Biveen Shajilal, Oliver Thearle, Aaron Tranter +5
Squeezed states are an interesting class of quantum states that have numerous applications. This work presents the design, characterisation, and operation of a bow-tie optical para…
Observation of entanglement between two light beams spanning an octave in optical frequency
Nicolai B. Grosse, Syed Assad, Moritz Mehmet +3
We have experimentally demonstrated how two beams of light separated by an octave in frequency can become entangled after their interaction in a second-order nonlinear medium. The…
A high fidelity heralded squeezing gate
Jie Zhao, Kui Liu, Jeng Hao +4
A universal squeezing gate capable of squeezing arbitrary input states is essential for continuous-variable quantum computation~\cite{PRA79062318,PRL112120504}. However, in present…
All-Gaussian State Discrimination Beyond the Coherent Helstrom Bound
Angus Walsh, Lorcan Conlon, Biveen Shajilal +5
A core problem in communications is the optimal discrimination of binary-phase-shift-keyed (BPSK) signals. A longstanding goal has been to reach the fundamental quantum limit, know…
Violation of Bells inequality using continuous variable measurements
Oliver Thearle, Jiri Janousek, Seiji Armstrong +8
A Bell inequality is a fundamental test to rule out local hidden variable model descriptions of correlations between two physically separated systems. There have been a number of e…
Improving Gaussian channel simulation using non-unity gain heralded quantum teleportation
Biveen Shajilal, Lorcán O. Conlon, Angus Walsh +5
Gaussian channel simulation is an essential paradigm in understanding the evolution of bosonic quantum states. It allows us to investigate how such states are influenced by the env…
Quantum-optimal information encoding using noisy passive linear optics
Andrew Tanggara, Ranjith Nair, Syed Assad +5
The amount of information that a noisy channel can transmit has been one of the primary subjects of interest in information theory. In this work we consider a practically-motivated…
Entropic Accord: A new measure in the quantum correlation hierarchy
Biveen Shajilal, Elanor Huntington, Ping Koy Lam +1
Quantum correlation often refers to correlations exhibited by two or more local subsystems under a suitable measurement. These correlations are beyond the framework of classical st…
Frequency-Division Multiplexed CV-QKD System
Jaehyeok Han, Donghyeok Lee, Minseok Ryu +3
We propose a frequency-division multiplexed (FDM) continuous-variable quantum key distribution (CV-QKD) system with enhanced spectral efficiency through optimized channel spacing o…
Strong cubic phase shifts on the photonic vacuum state
Hao Jeng, Lorcan Conlon, Ping Koy Lam +1
Addition of photons to coherent states is shown to produce effects that display remarkable similarities with cubic phase shifts acting on the vacuum state, with fidelities in exces…