Multi-zone parallel qubit addressing via multi-wavelength integrated photonics*

The integration of photonics within surface-electrode ion-trap chips could enable the development of larger quantum computers and portable quantum sensors. Recently, we demonstrated operation of an ion-trap chip where integrated photonics delivered all of the required wavelengths, from violet to infrared, necessary for control and read-out of Sr+ qubits[1]. Laser light was coupled onto the chip via an optical-fiber array, creating an inherently stable optical path that we use to demonstrate qubit coherence resilient to platform vibrations. Contemporaneously high fidelity two qubit gates using integrated photonics were also demonstrated [2]. Here we explore using multiple zones of interaction to perform parallel qubit operations on multiple ions using parallel integrated beam paths. Recent improvements to our photonics platform have improved our grating beam targeting accuracy, improved grating efficiency, reduced blue propagation loss and input coupling loss.
Niffenegger, R. J., et al. "Integrated multi-wavelength control of an ion qubit." Nature 586.7830 (2020): 538-542.
Mehta, Karan K., et al. "Integrated optical multi-ion quantum logic." Nature 586.7830 (2020): 533-537.