Publications

We make our research publically available through scientific papers and long-form theses. Feel free to download our works and do not hesitate to contact us if you need any information beyond what is written here.

Preprints

We make our papers available to the general public by publishing all preprints on the Physics arXiv.

S. Pucher, V. Klüsener, F. Spriestersbach, J. Geiger, A. Schindewolf, I. Bloch, and S. Blatt
Fine-Structure Qubit Encoded in Metastable Strontium Trapped in an Optical Lattice
We demonstrate coherent control of the fine-structure qubit in neutral strontium atoms. This qubit is encoded in the metastable ³P₂ and ³P₀ states, coupled by a Raman transition. Using a magnetic quadrupole transition, we demonstrate coherent state-initialization of this THz qubit. We show Rabi oscillations with more than 60 coherent cycles and single-qubit rotations on the μs scale. With spin-echo, we demonstrate coherence times of tens of ms. Our results pave the way for fast quantum information processors and highly tunable quantum simulators with two-electron atoms.
V. Klüsener, S. Pucher, D. Yankelev, J. Trautmann, F. Spriestersbach, D. Filin, S. G. Porsev, M. S. Safronova, I. Bloch, and S. Blatt
Coherent excitation of a μHz scale optical magnetic quadrupole transition
We report on the coherent excitation of the ultranarrow ¹S₀-³P₂ magnetic quadrupole transition in 88Sr. By confining atoms in a state insensitive optical lattice, we achieve excitation fractions of 97(1)% and observe linewidths as narrow as 58(1) Hz. With Ramsey spectroscopy, we find coherence times of 14(1) ms, which can be extended to 266(36) ms using a spin-echo sequence. We determine the linewidth of the M2 transition to 24(7) μHz, confirming longstanding theoretical predictions. These results establish an additional clock transition in strontium and pave the way for applications of the metastable ³P₂ state in quantum computing and quantum simulations.

Journal Articles

We make our papers available to the general public by publishing all preprints on the Physics arXiv.

  1. J. Trautmann, D. Yankelev, V. Klüsener, A. J. Park, I. Bloch, and S. Blatt
    ¹S₀-³P₂ magnetic quadrupole transition in neutral strontium
    Physical Review Research
    5
    013219
    2023

    arXiv
    2211.02470
  2. A. J. Park, J. Trautmann, N. Šantić, V. Klüsener, A. Heinz, I. Bloch, and S. Blatt
    Cavity-Enhanced Optical Lattices for Scaling Neutral Atom Quantum Technologies to Higher Qubit Numbers
    PRX Quantum
    3
    030314
    2022

    arXiv
    2110.08073
  3. A. Heinz, J. Trautmann, N. Šantić, A. J. Park, I. Bloch, and S. Blatt
    Crossed optical cavities with large mode diameters
    Optics Letters
    46
    250
    2021

    arXiv
    2011.01616
  4. A. Heinz, A. J. Park, N. Šantić, J. Trautmann, S. G. Porsev, M. S. Safronova, I. Bloch, and S. Blatt
    State-Dependent Optical Lattices for the Strontium Optical Qubit
    Physical Review Letters
    124
    203201
    2020

    arXiv
    1912.10350
  5. S. Snigirev, A. J. Park, A. Heinz, I. Bloch, and S. Blatt
    Fast and dense magneto-optical traps for strontium
    Physical Review A
    99
    063421
    2019

    arXiv
    1903.06435

PhD Theses

A PhD thesis in our group summarizes original work done over three to five years. Such a thesis is the perfect introduction to our field of research.

Jan Trautmann
The Magnetic Quadrupole Transition in Neutral Strontium
Fakultät für Physik der Ludwig-Maximilians-Universität München
2022
Annie Jihyun Park
Towards Quantum Simulations with Strontium in Cavity-enhanced Optical Lattices
Fakultät für Physik der Ludwig-Maximilians-Universität München
2021
André Heinz
Ultracold Strontium in State-Dependent Optical Lattices
Fakultät für Physik der Ludwig-Maximilians-Universität München
2020

Master’s Theses

A Master’s thesis in our group represents a full year’s worth of work in the lab. All theses describe significant original work by the author and are meant to be useful to other researchers in our field.

Andrew Whimster
A Two-Dimensional Magneto-Optical Trap for a Strontium Clock
Fakultät für Physik der Ludwig-Maximilians-Universität München
2023
Ömer Faruk Erşahan
A Laser System for Cavity-Enhanced State-Dependent Optical Lattices for Ultracold Strontium
Fakultät für Physik der Technischen Universität München
2023
Yilong Yang
A narrow-linewidth Laser System for the 1S0–3P2 Intercombination Transition in Strontium
Fakultät für Physik der Ludwig-Maximilians-Universität München
2021
Eva Casotti
A Two-dimensional Magneto-optical Trap for Strontium
Fakultät für Physik der Ludwig-Maximilians-Universität München
2020
Florian Wallner
New Tools for Controlling Strontium Atoms with High Spectral and Spatial Resolution
Fakultät für Physik der Technischen Universität München
2020
Rudolf Haindl
A Clock Laser System for Quantum Simulations with Ultracold Strontium Atoms
Fakultät für Physik der Ludwig-Maximilians-Universität München
2019
Etienne Staub
Developing a High-Flux Atomic Beam Source for Experiments with Ultracold Strontium Quantum Gases
Fakultät für Physik der Ludwig-Maximilians-Universität München
2019
Fabian Finger
A Transport Laser with Shape and Amplitude Control for Ultracold Strontium Atoms
Fakultät für Physik der Technischen Universität München
2018
Stephan Wissenberg
Stabilizing diode lasers to an ultrastable reference cavity
Fakultät für Physik der Ludwig-Maximilians-Universität München
2017
Rodrigo González Escudero
Magnetic Field Control and Laser Frequency Stabilization for Strontium Magneto-Optical Traps
Fakultät für Physik der Ludwig-Maximilians-Universität München
2016
Nejc Janša
A frequency-stable diode laser system for spectroscopy and trapping of Sr atoms
Fakultät für Physik der Ludwig-Maximilians-Universität München
2016

Bachelor’s theses

A Bachelor’s thesis in our group focuses on a specific technical topic that may be of interest to other researchers in our field. The work described in such a thesis spans ten weeks from the first day in the lab to the day the thesis is handed in.

Ivan Kokhanovskyi
Construction of an interference-filter-stabilized diode laser for experiments with ultracold strontium atoms
Fakultät für Physik der Ludwig-Maximilians-Universität München
2019
Lukas Homeier
Setup and characterization of a Littrow laser for 689 nm
Fakultät für Physik der Ludwig-Maximilians-Universität München
2017