NameResearch Description
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Sarang Gopalakrishnan

Current

email

It has recently become feasible to isolate and manipulate simple quantum-mechanical objects (e.g., single spins) experimentally. I am interested in the ways in which such simple objects can be assembled into controllable many-body systems, and what we can learn from such systems about questions of interest in condensed matter physics...

It has recently become feasible to isolate and manipulate simple quantum-mechanical objects (e.g., single spins) experimentally. I am interested in the ways in which such simple objects can be assembled into controllable many-body systems, and what we can learn from such systems about questions of interest in condensed matter physics. Examples of such questions in which I am currently interested include: 1. Crystallization and melting transitions driven by quantum fluctuations, the intermediate phases that arise during such transitions (i.e., quantum liquid crystals) and their distinctively quantum-mechanical properties. 2. Quantum dynamics away from thermal equilibrium, especially the dynamics of strongly disordered systems and systems with frustrated interactions (e.g., glasses), which are anomalously slow in their approach to equilibrium. 

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Kristiaan DeGreve

Current

email

My research interests are located at the interface between quantum optics and condensed matter, mesoscopic physics. My PhD work at Stanford focused on the ultrafast optical manipulation of single quantum dot spins1,2. As a postdoc, I intend to build on this quantum optics background to study condensed matter phenomena with quantum optical probes...

My research interests are located at the interface between quantum optics and condensed matter, mesoscopic physics. My PhD work at Stanford focused on the ultrafast optical manipulation of single quantum dot spins1,2. As a postdoc, I intend to build on this quantum optics background to study condensed matter phenomena with quantum optical probes. In particular, optically active nitrogen-vacancy (NV) defect centers in diamond have been shown to demonstrate excellent spin-coherence, even at room temperature, which would permit (sub)-single electron spin resolution on nm-lengthscales. By combining the expertise of the many Harvard groups working on NV-centers (Lukin, Yacoby, Hu, Loncar, Park, Walsworth,…), as well as the strong condensed matter research programs here, I hope to study the spin structure of exotic, correlated-electron systems, thereby shedding some light on the underlying physical mechanisms driving them. The workhorse tool for these studies would be the scanning NV-AFM magnetometer, which was recently developed in the Yacoby and Lukin groups3,4.

1 Quantum-dot spin–photon entanglement via frequency downconversion to telecom wavelength, K. De Greve et al, Nature 491, 421 (2012)
2 Ultrafast coherent control and suppressed nuclear feedback of a single quantum dot hole qubit, K. De Greve et al., Nature Physics 7, 872 (2011)
3 Nanoscale magnetic sensing with an individual electronic spin in diamond, J. R. Maze et al., Nature 455, 644 (2008)
4 A robust scanning diamond sensor for nanoscale imaging with single nitrogen-vacancy centres, P. Maletinsky, S. Hong, M. Grinolds et al., Nature Nanotechnology 7, 320 (2012)

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EKessler

Eric Kessler

now Scientist at IBM

email

The precise measurement of physical quantities is of great importance in science and technology with implications in a broad range of fields, ranging from tests of fundamental laws of physics, to nanoscale sensing in biological systems, and direct technological application such as the Global Positioning System (GPS)...

The precise measurement of physical quantities is of great importance in science and technology with implications in a broad range of fields, ranging from tests of fundamental laws of physics, to nanoscale sensing in biological systems, and direct technological application such as the Global Positioning System (GPS). My current research focuses on the development of novel metrological procedures using quantum mechanical resources and concepts from quantum information theory. For instance, building on our proposal to use quantum error correction to improve sensitivity in the presence of environmental noise, we are developing experimentally feasible protocols for the in-vivo detection of neuronal activity, using nanoscale, diamond-based electric field sensors. Furthermore, we investigate possibilities to use quantum informational concepts to facilitate the nanoscale imaging of macroscopic activation pattern in neuronal tissue.
Further areas of research comprise, e.g., the development of quantum enhanced clock protocols, in particular with the perspective of distributed networks for time and frequency metrology. In parallel to the metrological questions, I continue to pursue the work of my PhD studies in the context of coherent quantum phenomena in the nuclear spin systems of semiconductor nano-structures.

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Jelena Klinovaja

now Professor at University of Basel

email

My research plan is to propose and to work on schemes in condensed matter systems that could serve as a platform for quantum information processing. The main direction I am going to pursue is spin-based quantum computation: topological and non-topological. At the heart of this lies the spin orbit interaction, a relativistic effect that is responsible for many fascinating phenomena discovered recently, such as topological
insulators, Majorana fermions, parafermions, and spin effects in strongly correlated materials and in optical lattices...

My research plan is to propose and to work on schemes in condensed matter systems that could serve as a platform for quantum information processing. The main direction I am going to pursue is spin-based quantum computation: topological and non-topological. At the heart of this lies the spin orbit interaction, a relativistic effect that is responsible for many fascinating phenomena discovered recently, such as topological
insulators, Majorana fermions, parafermions, and spin effects in strongly correlated materials and in optical lattices. The focus of my PhD work done at the University of Basel has been on spin phenomena, and I plan to continue to work in this area. In particular, I am interested in engineering setups in which Majorana fermions, parafermions, or fractional fermions can be detected unambiguously. The RKKY systems are potential
candidates for many new interesting phenomena, both interesting for classical and topological computational schemes, so I am going to pursue my research also in this direction.

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Thibault Peyronel

Current

email

I am in interested in experimental quantum optics, with a focus on quantum information science. The ability to control light and its interaction with matter at the quantum level holds exciting promises for quantum computation and metrology. During my PhD at MIT, I worked on creating cold atomic media exhibiting optical nonlinearities at the single photon level...

I am in interested in experimental quantum optics, with a focus on quantum information science. The ability to control light and its interaction with matter at the quantum level holds exciting promises for quantum computation and metrology. During my PhD at MIT, I worked on creating cold atomic media exhibiting optical nonlinearities at the single photon level. One successful approach consists in coupling individual photons to strongly interacting atomic states, known as Rydberg atoms, using so-called Electromagnetically Induced Transparency techniques [Nature 488,57–60(2012)],[Nature 502,71–75(2013)].
Alternatively, atom-photon interactions can be strongly enhanced by optical resonators. The fascinating properties resulting from these enhanced interactions have led to remarkable achievements in the field of Cavity QED. Nano-fabrication techniques have enabled a new class of optical resonators, known as photonic crystals, in which light is manipulated on a sub-wavelength scale, paving the way for integrated quantum networks. I have joined the current effort in the Lukin and Loncar groups to explore the new interfaces provided by the coupling of coherently controlled atoms to photonic nano-structures. In particular, I am focusing on experiments using cold neutral atoms and NV centers in diamond

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Marton Kanász-Nagy

Current

email

I am primarily interested in correlations in many-body quantum systems. During my PhD, I worked on certain aspects of interactions, correlated and topological phases of ultracold gases. Building on these experiences as a postdoc, I intend to broaden my interest to a wider range of condensed matter systems...

I am primarily interested in correlations in many-body quantum systems. During my PhD, I worked on certain aspects of interactions, correlated and topological phases of ultracold gases. Building on these experiences as a postdoc, I intend to broaden my interest to a wider range of condensed matter systems. Currently, I am especially interested in non-equilibrium dynamics, in particular in the theoretical description of resonant inelastic x-ray scattering (RIXS) experiments. Recent technological developments has made RIXS a versatile and powerful probe of spin, charge and superconducting correlations in a range of high-temperature superconductors, potentially leading to deeper understanding of these complex materials. It is thus rather interesting for me to look into the theoretical description of these experiments, especially, to understand the effects of electron-electron and electron-phonon interactions. Besides this line of research, I intend to continue working in the field of atomic molecular and optical physics, for which the Harvard Quantum Optics Center will provide an ideal environment.

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Sebastian Blatt

Sebastian Blatt

Current

email

My PhD work has focused on a next generation atomic clock based on a narrow optical transition in neutral strontium trapped in an optical lattice. These novel systems based on fermionic strontium-87 are at the intersection of precision metrology and many-body physics, enabling studies of as seemingly diverse topics as tests of the variation of fundamental constants [1], or the suppression of interaction-induced clock frequency shifts by enhancing the interactions [2]...

My PhD work has focused on a next generation atomic clock based on a narrow optical transition in neutral strontium trapped in an optical lattice. These novel systems based on fermionic strontium-87 are at the intersection of precision metrology and many-body physics, enabling studies of as seemingly diverse topics as tests of the variation of fundamental constants [1], or the suppression of interaction-induced clock frequency shifts by enhancing the interactions [2].

[1] Strontium lattice clocks constrain present day drifts of fundamental constants and their coupling to the ambient gravitational potential, Physical Review Letters 100, 140801 (2008).

[2] Suppression of Collisional Shifts in a Strongly Interacting Lattice Clock, Science Express (February 3rd, 2011)

I intend to work with the group of Markus Greiner on a new type of quantum gas microscope for neutral lithium-6 atoms. Individual atoms will be interrogated with a novel submicron imaging technique based on selective photoionization and fragment detection. This method will offer high-fidelity detection of single atoms on individual lattice sites without perturbing neighboring sites, and lends itself to the implementation of novel superresolution techniques. The proposed microscope is an extension to a lithium quantum gas apparatus that is currently being built in the research group of Prof. Greiner. It could enable the first direct detection of fermionic band and Mott insulators in optical lattices, and would allow direct measurements of correlations in quantum magnetism, for example in the predicted antiferromagnetic phases.

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Nicholas Hutzler

Current

email

Ultracold atoms have provided some of the deepest insights into quantum, many-body, and fundamental physics. Extending the techniques of ultracold atomic physics to molecules is complicated by their rich internal structure, but this structure is also why so many physicists are trying to achieve this goal...

Ultracold atoms have provided some of the deepest insights into quantum, many-body, and fundamental physics. Extending the techniques of ultracold atomic physics to molecules is complicated by their rich internal structure, but this structure is also why so many physicists are trying to achieve this goal. I am working with the Ni group to create systems of individual, fully-controlled polar molecules. We will start with single atoms trapped in tightly-focused optical tweezers, then coherently combine the individual atom pairs to create molecules. This technique will allow us to create systems of polar molecules that can be prepared and read out individually, with full control over the internal states, position, and interactions.

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Ofer Firstenberg

Ofer Firstenberg

now Member of the Faculty at Weizmann Institute

email

In recent years, I have been working in the field of quantum optics with thermal vapor, carrying out both theoretical and experimental research in coherent multi-photon processes, atomic collisions, slow and stored light, and quantum-technology applications. I received my PhD from the Technion-Israel Institute of Technology for my study on spatial phenomena in electromagnetically induced transparency...

In recent years, I have been working in the field of quantum optics with thermal vapor, carrying out both theoretical and experimental research in coherent multi-photon processes, atomic collisions, slow and stored light, and quantum-technology applications. I received my PhD from the Technion-Israel Institute of Technology for my study on spatial phenomena in electromagnetically induced transparency. I have investigated the diffusion of atomic coherence in complex transverse modes [Phys. Rev. Lett. 105, 183602 (2010)], spectral broadening and narrowing mechanisms in alkali gases, diffraction manipulation and diffusion of light-matter polaritons [Nature Physics 5, 665-668 (2009)], and motional-induced vector potential for light. As a researcher in the quantum-optics group at Rafael LTD in Israel, I have experienced with entanglement, non-classical light, and quantum measurement theories, and worked on atomic frequency-standards and magentometers.

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Johannes Otterbach

Johannes Otterbach

now at Planatir Technologies

email

Up to now photonic interactions are mostly restricted to so-called Kerr-type nonlinearities resulting in point interactions. These only become strong in the limit of large transverse con nement limiting the observation of strong interaction e ects to 1D systems. It remains a challenging task to create strong and long-range interactions for photons in higher dimensions and without the need of large confinement...

Up to now photonic interactions are mostly restricted to so-called Kerr-type nonlinearities resulting in point interactions. These only become strong in the limit of large transverse con nement limiting the observation of strong interaction e ects to 1D systems. It remains a challenging task to create strong and long-range interactions for photons in higher dimensions and without the need of large confinement. The recent advance in coherent control and manipulation of atomic or molecular ensembles with strong long-range interactions, using e.g. Rydberg atoms, makes it possible to tackle this challenge. Analogous to the case of cold atoms the use of Rydberg atoms leads to effective long-range interactions between polaritons. Moreover the polaritons present a versatile probe for these systems since the strong correlations directly map to the photonic component of the polaritons. This opens up the opportunity to study strongly interacting photons in any dimension with possible applications in the creation of exotic states and in quantum information.

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Jay Deep Sau

Jay Deep Sau

now Assistant Professor – University of Maryland

email

I am a condensed matter theorist. My PhD thesis work at Berkeley till 2008 was spread over several areas of condensed matter physics including electronic structure, mesoscopic superconductivity and spinor cold atomic gases [1]. My postdoctoral work since 2009 at Maryland has focused on realizing Topological Superconductors and Majorana Fermions...

I am a condensed matter theorist. My PhD thesis work at Berkeley till 2008 was spread over several areas of condensed matter physics including electronic structure, mesoscopic superconductivity and spinor cold atomic gases [1]. My postdoctoral work since 2009 at Maryland has focused on realizing Topological Superconductors and Majorana Fermions. In 2009-10, we proposed a generic class of semiconductor structures with spin-orbit coupling in the vicinity of conventional s-wave superconductors to realize Majorana Fermions [2,3]. Over the past year, we have used the rather extensive knowledge on conventional superconductors and semiconductors to understand various aspects of the physics of Majorana fermions and non-Abelian statistics.

[1] Theory of domain formation in inhomogeneous ferromagnetic dipolar condensates within the truncated Wigner approximation, Jay D. Sau, S. R. Leslie, D. M. Stamper-Kurn, and Marvin L. Cohen, Phys. Rev. A 80, 023622 (2009)

[2] Generic New Platform for Topological Quantum Computation Using Semiconductor Heterostructures, Jay D. Sau, Roman M. Lutchyn, Sumanta Tewari, and S. Das Sarma, Phys. Rev. Lett. 104, 040502 (2010)

[3] Non-Abelian quantum order in spin-orbit-coupled semiconductors: Search for topological Majorana particles in solid-state systems, Jay D. Sau, Sumanta Tewari, Roman M. Lutchyn, Tudor D. Stanescu, and S. Das Sarma, Phys. Rev. B 82, 214509 (2010)

Given my broad interests in condensed matter theory, I hope to collaborate with the entire condensed matter theory group at Harvard and in particular work with Prof Bert Halperin on topological systems, Prof Subir Sachdev on quantum criticality and Prof Eugene Demler on cold atomic systems. Condensed matter experimentalists at Harvard are actively studying potentially topologically interesting systems that I am also currently working on. Therefore I plan to continue my current research on topological superconducting systems, in active collaboration with experimentalists, to develop experimentally realizable structures that would support Majorana fermions and understand their properties. Cold atomic systems, which have been one of my central interests, also provide very promising realizations of topological superconductors. This promise is accentuated by the recent experimental demonstration of spin-orbit coupling in cold atomic systems. By collaborating with Prof Demler and the rest of the Center for Ultra Cold Atoms, I hope to help develop ways to detect Majorana fermions in cold atomic systems. Finally, I am excited about the development of classes of materials where strong interactions lead to instabilities of fermionic systems such as superconductivity and magnetism. I hope to work with Prof Subir Sachdev to learn more about such systems and possibly understand the role of topology and mathematical techniques such as the AdS/CFT correspondence in interacting systems.

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