Ultraviolet laser pulses with multigigahertz repetition rate and multiwatt average power for fast trapped-ion entanglement operations Articles uri icon


  • Hussain, Mahmood Irtiza
  • Heinrich, Daniel
  • Guevara-Betsch, Milena
  • García-Ripoll, Juan José
  • Roos, Christian F.
  • Blatt, Rainer

publication date

  • February 2021

start page

  • 1

end page

  • 9


  • 2


  • 15

International Standard Serial Number (ISSN)

  • 2331-7019


  • The conventional approach to perform two-qubit gate operations in trapped ions relies on exciting the ions on motional sidebands with laser light, which is an inherently slow process. One way to implement a fast entangling gate protocol requires a suitable pulsed laser to increase the gate speed by orders of magnitude. However, the realization of such a fast entangling gate operation presents a big technical challenge, as such the required laser source is not available off-the-shelf. For this, we have engineered an ultrafast entangling gate source based on a frequency comb. The source generates bursts of several hundred mode-locked pulses with pulse energy ∼800 pJ at 5 GHz repetition rate at 393.3 nm and complies with all requirements for implementing a fast two-qubit gate operation. Using a single, chirped ultraviolet pulse, we demonstrate a rapid adiabatic passage in a Ca+ ion. To verify the applicability and projected performance of the laser system for inducing entangling gates we run simulations based on our source parameters. The gate time can be faster than a trap period with an error approaching 10−4.


  • Physics