The fractional quantum anomalous Hall (FQAH) effect was recently discovered in twisted MoTe2 bilayers (tMoTe2)1–4. Experiments to date have revealed Chern insulators from hole doping at ν =-1,-2/3,-3/5, and-4/7 (per moiré unit cell) 1–6. In parallel, theories predict that, between v =-1 and-3, there exist exotic quantum phases 7–15, such as the coveted fractional topological insulators (FTI), fractional quantum spin Hall (FQSH) states, and non-abelian fractional states. Here we employ transient optical spectroscopy 16,17 on tMoTe2 to reveal nearly 20 hidden states at fractional fillings that are absent in static optical sensing or transport measurements. A pump pulse selectively excites charge across the correlated or pseudo gaps, leading to the disordering (melting) of correlated states 18. A probe pulse detects the subsequent melting and recovery dynamics via exciton and trion sensing 1,3,19–21. Besides the known states, we observe additional fractional fillings between ν = 0 and-1 and a large number of states on the electron doping side (ν 0). Most importantly, we observe new states at fractional fillings of the Chern bands at ν =-4/3,-3/2,-5/3,-7/3,-5/2, and-8/3. These states are potential candidates for the predicted exotic topological phases 7–15. Moreover, we show that melting of correlated states occurs on two distinct time scales, 2–4 ps and 180–270 ps, attributed to electronic and phonon mechanisms, respectively. We discuss the differing dynamics of the electron and hole doped states from the distinct moiré conduction and valence bands.
Category: quantum physics – Page 5
In a jaw-dropping scientific development, scientists are now exploring how to teleport an entire human using quantum technology. What began as a theory in 1993 is now becoming tangible thanks to quantum teleportation, which allows the transfer of quantum states — not matter — across vast distances. Though the dream of instant human transfer remains full of challenges, the progress is real, and the implications are as exciting as they are unsettling.
There are a seemingly endless number of quantum states that describe quantum matter and the strange phenomena that emerge when large numbers of electrons interact. For decades, many of these states have been theoretical: mathematical and computational predictions potentially hiding among real-life materials—a zoo, as many scientists are coming to refer to it, with new “species” just waiting to be discovered and described.
In a new study published on April 3 in Nature, researchers added over a dozen states to the growing quantum zoo.
“Some of these states have never been seen before,” said lead author Xiaoyang Zhu, Howard Family Professor of Nanoscience at Columbia. “And we didn’t expect to see so many either.”
Quantum magnetometers can detect incredibly small changes in magnetic fields by tapping into the strange and powerful features of quantum physics. These devices rely on the discrete nature and coherence of quantum particles—behaviors that give them a major edge over classical sensors. But how far can their sensitivity go? And what actually makes a magnetometer “quantum?”
A new study explores the theoretical boundaries of these devices, comparing multiple methods for defining their limits. The findings shed light not only on performance but also on what truly separates quantum sensors from their classical counterparts.
Quantum Magnetometers and Ultra-High Sensitivity.
Researchers have achieved a major leap in quantum computing by simulating Google’s 53-qubit Sycamore circuit using over 1,400 GPUs and groundbreaking algorithmic techniques. Their efficient tensor network methods and clever “top-k” sampling approach drastically reduce the memory and computational
A team of researchers at Q-CTRL, a quantum infrastructure software-maker based in Sydney, Australia, has announced the successful demonstration of its newly developed quantum navigation system called “Ironstone Opal.”
The group has written a paper describing how their system works and how well it tested against currently available backup GPS systems and has posted it on the arXiv preprint server.
With the advent and subsequent reliance on GPS by private and military vehicles and aircraft for navigation, governments have come to understand how vulnerable such systems can be. Outages can lead to drivers being stranded, pilots scrambling to use outdated systems and difficulties deploying military assets. Because of that, scientists around the world have been looking for reasonable backup systems, or even possible alternatives to GPS.
This essay advances a speculative yet empirically-grounded hypothesis: that microtubular cytoskeletal structures constitute proto-cognitive architectures in unicellular organisms, thereby establishing an evolutionary substrate for cognition that predates neural systems. Drawing upon converging evidence from molecular biology, quantum biophysics, phenomenological philosophy, and biosemiotic theory, I propose a cytoskeletal epistemology wherein cognition emerges not exclusively from neural networks, but from the dynamic, embodied information-processing capacities inherent in cellular organization itself. This framework challenges neurocentric accounts of mind while suggesting new avenues for investigating the biological foundations of knowing.
Contemporary cognitive science predominantly situates the genesis of mind within neural tissue, tacitly assuming that cognition emerges exclusively from the electrochemical dynamics of neurons and their synaptic interconnections. Yet this neurocentric paradigm, while experimentally productive, encounters both conceptual and empirical limitations when confronted with fundamental questions regarding the biological preconditions for epistemic capacities. As Thompson (2007) observes, “Life and mind share a set of basic organizational properties, and the organizational properties distinctive of mind are an enriched version of those fundamental to life” (p. 128). This suggests a profound continuity between biological and cognitive processes — a continuity that invites investigation into pre-neural substrates of cognition.
The present inquiry examines the hypothesis that the microtubule — a foundational cytoskeletal element ubiquitous across eukaryotic cells — functions not merely as mechanical infrastructure but as an evolutionary precursor to cognitive architecture, instantiating proto-epistemic capacities in unicellular and pre-neural multicellular organisms. This hypothesis emerges at the intersection of multiple research programs, including quantum approaches to consciousness (Hameroff & Penrose, 2014), autopoietic theories of cognition (Maturana & Varela, 1980), and recent advances in cytoskeletal biology (Pirino et al., 2022).
Give me a qubit for long enough and a probe in which to measure it, and I shall extract the geometry of our world.
At the quantum level, the past and the future are indiscernible. That could have profound effects on the world we can see.
Quantinuum’s 56-bit trapped-ion computer has succeeded in demonstrating randomness in quantum circuits to establish secure, private connections