QuCSI

Quantum Adaptive Agents with Efficient Long-Term Memories (Phys. Rev. X 12, 011007)

To thrive in ever-changing environments, systems must be able to adapt their actions to respond appropriately to the stimuli they receive. These adaptive systems, or agents, exist at all scales, from microscopic bacteria to self-driving vehicles. Common to all is that they interact and compete with other agents, mounting a drive to develop and deploy ... Read moreQuantum Adaptive Agents with Efficient Long-Term Memories (Phys. Rev. X 12, 011007)

Thermodynamic machine learning through maximum work production

In this work, we decided to look at the relations between two seemingly rather disconnected concepts - free energy extraction, and machine learning. it turns out though, that the two concepts hold rich relations. Notably, for a demon to be able to extra the greatest work from a pattern, he needs to have a mental ... Read moreThermodynamic machine learning through maximum work production

Impossibility of achieving Landauer's bound for almost every quantum state

The thermodynamic cost of resetting an arbitrary initial state to a particular desired state is lower bounded by Landauer's bound. However, here we demonstrate that this lower bound is necessarily unachievable for every initial state (except possibly the single minimally dissipative input) for any reliable reset mechanism. Since local heating threatens rapid decoherence, this issue ... Read moreImpossibility of achieving Landauer's bound for almost every quantum state

Interfering trajectories in experimental quantum-enhanced stochastic simulation Nature Communications, 10, 1630)

In the 2018 movie Infinity War, a scene featured Dr. Strange looking into 14 million possible futures to search for a single timeline where the heroes would be victorious. Perhaps he would have had an easier time with help from a quantum computer. In with work, we worked with colleagues from Griffith university to constructed ... Read moreInterfering trajectories in experimental quantum-enhanced stochastic simulation Nature Communications, 10, 1630)

Quantifying memory capacity as a quantum thermodynamic resource (Phys. Rev. Lett. 122, 060601)

The Szilard Engine presented the iconic example that related information theory and thermodynamics. In this engine, it was shown that when a demon is supplied with a 'blank tape' to record information, he could use it as a resource to do work. Here, we looked at what happens to such a demon when he is ... Read moreQuantifying memory capacity as a quantum thermodynamic resource (Phys. Rev. Lett. 122, 060601)

Memory-efficient tracking of complex temporal and symbolic dynamics with quantum simulators (New Journal of Physics 21, 013021)

We know from prior works that quantum models have an advantage when it comes to generating predictions, using less memory than all classical counterparts. This was first done in the context of processes that output symbols at discrete points in time. Subsequently similar advantages were discovered processes that can emit only a single symbol, but ... Read moreMemory-efficient tracking of complex temporal and symbolic dynamics with quantum simulators (New Journal of Physics 21, 013021)

Matrix Product States for Quantum Stochastic Modelling (Phys. Rev. Lett. 121, 260602)

There are many notions of complexity and structure. In computational mechanics, for example, the complexity of a stochastic process can be characterized by how much information one must store about its past to general future statistical predictions faithfully. Meanwhile, in quantum any body systems, a prominent measure of complexity is in the amount of information ... Read moreMatrix Product States for Quantum Stochastic Modelling (Phys. Rev. Lett. 121, 260602)

Operational Resource Theory of Continuous-Variable Nonclassicality (Phys. Rev. X 8, 041038)

Photons in the quantum realm behave very differently from the classical light experienced in our everyday lives. The concept of nonclassicality—one of the most influential ideas of twentieth-century quantum physics—draws a boundary between these two regimes. Nonclassical light is also a valuable resource, underpinning exciting technologies that exploit the peculiarities of quantum physics, including ultrasensitive ... Read moreOperational Resource Theory of Continuous-Variable Nonclassicality (Phys. Rev. X 8, 041038)

Operational resource theory of continuous-variable nonclassicality

Photons in the quantum realm behave very differently from the classical light experienced in our everyday lives. The concept of nonclassicality—one of the most influential ideas of twentieth-century quantum physics—draws a boundary between these two regimes. Nonclassical light is also a valuable resource, underpinning exciting technologies that exploit the peculiarities of quantum physics, including ultrasensitive ... Read moreOperational resource theory of continuous-variable nonclassicality