Interview With a Nobel Prize Winner

The Nobel Prize in Physics 1985 was awarded to Prof. Klaus von Klitzing for the discovery of the quantized Hall effect. This is evident in electronic systems at the nanoscale, e.g., in transistors having the conducting channel realized at the surface of the semiconductor or with 2D graphene layers. Nowadays, hundreds of millions of sensors sold each year are based on the Hall effect. They are mainly used as magnetic/current sensors, proximity or positioning sensors, and speed detectors. And they are often integrated in CMOS (Complementary Metal-Oxide Silicon) chips. Hall sensors are commercially available as fully integrated systems alongside their sensor interfaces. Market figures show a total value close to a billion US dollars, worldwide. Therefore, it has been a great honor to talk with Prof. Klaus von Klitzing and going back with him to the exciting moments when he noticed the first evidence of his fascinating discovery. This article reports the details of such a kind conversation.