Periodic Reporting for period 1 - CORSAIR (Controlled subradiance in atomic arrays)
Période du rapport: 2022-09-01 au 2025-02-28
The understanding of the interaction of light with ensembles of atoms is a hard, quantum many-body problem. However understanding this problem is vital to describe many phenomena where matter made of many individual emitters interacts with light. In addition, it might have a significant impact for quantum technologies. Indeed, novel quantum simulators based on atomic arrays have been developed, based on atomic arrays trapped in optical tweezer. Understanding how these arrays collectively interact with light is an interesting challenge, and might unlock new applications for these simulators.
The goal of the CORSAIR project is to develop a dedicated experiment to understand the collective interaction of an atomic array with light. For this, one needs an apparatus able to prepare arrays of atoms, to control their interaction with light, and to measure how the interaction with light modifies the array. In particular, when the array is impinged on by light, this light induces interactions between the atoms, which modify the state of the array, and induces a collective response that differs drastically to the response of an individual atom. Within the CORSAIR project, we will fully control the light-matter interaction of the individual atoms with light. Furthermore we will setup new methods to probe in-situ how light-induced interactions modify the atomic state, which is key to understand their collective response to light. Once these tools are in place, we will perform dedicated experiments, in the regime where the distance between the atoms is shorter than the wavelength of the light, which is where strong effects are expected. We will perform experiments on spectroscopy and collective spontaneous emission. Understanding these effects is crucial for metrology (precise measurements) in atomic physics, or to leverage collective effects in quantum simulators.
The goal of the CORSAIR project is to develop a dedicated experiment to understand the collective interaction of an atomic array with light. For this, one needs an apparatus able to prepare arrays of atoms, to control their interaction with light, and to measure how the interaction with light modifies the array. In particular, when the array is impinged on by light, this light induces interactions between the atoms, which modify the state of the array, and induces a collective response that differs drastically to the response of an individual atom. Within the CORSAIR project, we will fully control the light-matter interaction of the individual atoms with light. Furthermore we will setup new methods to probe in-situ how light-induced interactions modify the atomic state, which is key to understand their collective response to light. Once these tools are in place, we will perform dedicated experiments, in the regime where the distance between the atoms is shorter than the wavelength of the light, which is where strong effects are expected. We will perform experiments on spectroscopy and collective spontaneous emission. Understanding these effects is crucial for metrology (precise measurements) in atomic physics, or to leverage collective effects in quantum simulators.
In the two first years of the action, we have built an apparatus capable of preparing single atoms in optical tweezers and to measure their state in a single shot to perform collective light-matter interactions in the arrays.
The atomic species we use is dysprosium (Dy). We have picked this species for its unique features in terms of interaction with light: Dy has many lines with different wavelength and width in its spectrum, which means that on can use different lines for different usages. We have leveraged this spectrum to find a way to trap single Dy atoms in optical tweezers, and produced arrays of single atoms. Then we have setup a method to measure very fast how the state of each individual atoms is modified while the array interacts with light. This single-shot state readout is key to perform the goals of the CORSAIR project. This has allowed us to start performing the first experiments of spectroscopy of an array of single atoms, with the ability to resolve each atom's state.
The atomic species we use is dysprosium (Dy). We have picked this species for its unique features in terms of interaction with light: Dy has many lines with different wavelength and width in its spectrum, which means that on can use different lines for different usages. We have leveraged this spectrum to find a way to trap single Dy atoms in optical tweezers, and produced arrays of single atoms. Then we have setup a method to measure very fast how the state of each individual atoms is modified while the array interacts with light. This single-shot state readout is key to perform the goals of the CORSAIR project. This has allowed us to start performing the first experiments of spectroscopy of an array of single atoms, with the ability to resolve each atom's state.
Trapping and imaging of individual atoms is a powerful tool for quantum physics studies. Before the CORSAIR project, it had been performed on atomic species (or molecules) with a single or two electrons in their outer shell. In the action we had to develop new methods to trap and image single Dy atoms. Dy is a lanthanide species, specific for having many electrons in their outer-shell. By using the peculiarity of the lanthanide family we were able to find methods to trap and image single atoms in optical tweezers. This has opened the path for the usage of the optical tweezers palette to lanthanide species (experiments have been performed with erbium since then). This family of species features interesting properties, for light-matter studies, but also for quantum science in general such as quantum magnetism or metrology, and we expect many studies with lanthanides in optical tweezers.