The vacuum tubes in Dirk Englund’s lab may look like the vacuum tubes used in the first digital electronic computers. But these bulky devices may well herald the dawn of a new age in technology: the long-promised age of quantum computing. “Quantum computing isn’t just about faster computing,” says Englund, the Jamieson Career Development Professor in Electrical Engineering and Computer Science. “Quantum information processing will enable activities in communications, computing, sensing, and drug discovery that aren’t possible with today’s or even tomorrow’s computers.”
Working with neuroscientist Edward Boyden ’99, MNG ’99—a faculty member affiliated with the MIT Media Lab, the departments of brain and cognitive sciences and biological engineering, and the McGovern Institute for Brain Research—Englund is using the power of quantum computing to develop a new class of noninvasive optical probes that could help reveal how the brain processes information. The team works with small pieces of diamond that contain a defect made of an embedded nitrogen atom. When stimulated by an electromagnet, this N-V defect reacts much the way a compass reacts within a magnetic field, providing information about the external field and the underlying phenomena that are creating that field.
Applied to neuroscience, the resulting atomic and subatomic spins observed in these nanodiamonds could eventually be used to monitor neural cell signaling—the exchange of positive and negative ions in the human brain that constitute the basis of brain activity. At present, this activity can only be captured by inserting an electrode into the brain.