ion-channel

Our current focus

Ion-channels are the fundamental building blocks of brain’s electrical activity, providing the pathway for ion flux through the neuron’s membrane. There appear to be a number of processes in single-ion-channel electrophysiology that are promising when looked upon at the microscopic, quantum level.

lab_neuron

Our contributions

We are currently developing a state-of-the-art electrophysiology facility, consisting of optical microscopes (inverted and stereo), electronic micro manipulation, computer-controlled pA current amplifiers with data acquisition software and a modern laser-based micro-pipette fabrication device.

intro_neuro

Introduction

We are convinced that future breakthroughs in quantum biology will emanate from neuroscience, which offers numerous complex processes at the proper time and length scale to look for quantum effects. We are therefore investing in this direction for the long-term development of our research.

spin_current

Our current focus

Instead of using the indirect signature of increased spin-noise power, we wish to directly demonstrate the spin-noise correlations that spontaneously emerge in multi-species vapors and further study their ramifications for measurement precision in spin-exchange dominated atomic vapors. Studying this effect at even lower magnetic fields where the magnetic resonance line width is not anymore dominated by spin-exchange is a natural next step. We would also like to connect these studies with the general goal of quantum metrology of achieving sub-shot-noise spin fluctuations towards enhancing the precision of spin measurements such as in atomic magnetometers.

SN_Setup

Our contributions

We focused on high resolution measurements of spin noise at low magnetic fields, showing how one can obtain information about spin relaxation from the spontaneous spin noise resonance width. Most recently, we have demonstrated a new phenomenon related to spin-exchange collisions, namely that in a multi-species atomic vapor and low magnetic fields, spin-exchange collisions induce positive inter-species spin-noise correlations. This is an extension in the realm of quantum fluctuations of the well known property of spin exchange, the inter-species transfer of a deterministic spin polarization. The new effect, termed spin-noise exchange, was revealed by a low-field increase of the total spin-noise power.

cell

Introduction

Manipulating the spin degrees of freedom of atomic vapors has in recent years led to exciting advances in atomic physics and quantum metrology. In particular, understanding spin relaxation phenomena in collision-dominated atomic vapors, like cesium vapors used in atomic clocks, has lead to novel ultrasensitive magnetometers, having a number of applications, from low-field NMR to biomagnetic imaging. One of the fundamental limitations of this kind of precision measurements is spontaneous spin noise. This is a quantum fluctuation of the atomic vapor’s collective spin driven by atomic collisions, and sets the noise level and hence the precision of all relevant spin measurements.

qubio_current

Our current focus

We currently pursue our theoretical research along the two major fronts of quantum biology, the radical-pair mechanism and photosynthesis. We believe that there is a whole lot more to discover in the quantum dynamics relevant to these two themes, especially in the albeit difficult to establish connection between microscopic quantum dynamics and macroscopic biological observations. Questions like the fundamental quantum limits to the avian compass mechanism and the charge and energy transport efficiency in photosynthesis are central for our work. Whether real biological systems actually achieve those limits and if not, how to design and build artificial systems that do also forms a major avenue of current and future research in our group, a direction that we term quantum bio-engineering.

RP_model

Our contributions

We were one among the few groups that pioneered the field of quantum biology. We introduced the study of the fundamental quantum dynamics of the radical-pair mechanism. Radical-ion-pair reactions are spin-dependent biochemical reactions relevant to photosynthesis and the avian magnetic compass. The radical-pair mechanism, the cornerstone of the field of spin chemistry, was known since the 60’s. Our group was the first to unravel the rich quantum-information science behind this biological mechanism, showing that concepts like quantum measurements, the quantum Zeno effect, measures of quantum coherence and even the quantum-communications concept of quantum retrodiction are necessary to understand the underlying quantum dynamics of radical-pairs.

rb1

Introduction

Quantum biology is a new swiftly growing scientific synthesis merging quantum information science with the richness and complexity of biological systems. Recent theoretical and experimental evidence supports the early intuition of the founding fathers of quantum mechanics that biological systyems should be influenced by the intricacies of quantum physics. Currently, quantum biology is explored mainly along three fronts: photosynthesis, magnetoreception and olfaction. Quantum biology is not about the “static”, atomistic aspect of biological structure but about dynamic effects related to quantum coherence and entanglement influencing biological function. Quantum biology is a uniquely interdisciplinary field combining quantum science, physical chemistry, biochemistry and biology.