New Quantum Materials

New Materials

The goal of this research thrust is the development of novel quantum nanoprobes that enable sensitive detection of charge and/or spin fluctuations at a nanometer length scale. Ultrasmall quantum nanoprobes can be chemically modified for efficient targeting of biomolecules and delivery to subcellular sites. These nanoprobes will advance investigations of biological questions not accessible by conventional technologies.

Approach

  • Task 1: We will investigate three different yet complementary crystallographic defect systems: sub-10-nm sized diamond nanocrystals hosting NV centers; other high-bandgap semiconductors (silicon carbide (SiC)); and optically active ionic defects in water and amorphous ice. As the best-studied crystallographic defect system, diamond-based defects are an excellent model for our investigation. While creation of ultrasmall crystals with optically active NV centers and sufficiently long coherence times can be challenging, SiC can be more readily synthesized in small colloidal form. Defects in SiC have been shown to be near analogues of the diamond NV centers, with the added advantages of better spin coherence and photoluminescent emission in a biological window. Ionic defects in solution, although the least studied systems, are in many senses similar to crystallographic defects but without the challenges associated with a crystalline host, such as large size (tens to hundred nanometers) and complex surface chemistry.
  • Task 2: Similar to crystallographic defects, molecular systems can have coherence times on the order of a few microseconds, and, like color centers, can be optically addressed and readout at a single spin level.60,61 However, molecular systems are largely underexplored in the context of quantum information technology and quantum sensing.3 Molecular qubit sensors are significantly smaller than nanoparticles (translates into increased sensitivity), their optical and spin properties can be engineered through chemical synthesis,3 and they can be efficiently conjugated to biological targets.