Heinrich Barkhausen
Encyclopedia
Heinrich Georg Barkhausen (December 2, 1881 – February 20, 1956), born at Bremen, was a German
physicist.
Born into a patrician family in Bremen, he showed interest in natural sciences from an early age. He studied at the Technical University of Munich
(1901), TU Berlin (1902) and University of Munich (1903) and Berlin
before obtaining a doctorate at the University of Göttingen in 1907.
He became Professor for Electrical Engineering at the Technische Hochschule Dresden in 1911 at the age of 29, thus obtaining the world's first chair in this discipline.
He discovered in 1919 an effect named after him, the Barkhausen effect
, which suggested that ferromagnetic materials contain regions of like-oriented atoms. Induced changes in the magnetic orientation of these domains affect the whole domain and not individual atoms. With suitable equipment, these changes of orientation (jumps) can be heard.
The Barkhausen stability criterion
states that an oscillator will oscillate when the total phase shift
from input to output back to input is an integral multiple of 360 degrees and the system gain is equal to 1.
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
physicist.
Born into a patrician family in Bremen, he showed interest in natural sciences from an early age. He studied at the Technical University of Munich
Technical University of Munich
The Technische Universität München is a research university with campuses in Munich, Garching, and Weihenstephan...
(1901), TU Berlin (1902) and University of Munich (1903) and Berlin
Berlin
Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...
before obtaining a doctorate at the University of Göttingen in 1907.
He became Professor for Electrical Engineering at the Technische Hochschule Dresden in 1911 at the age of 29, thus obtaining the world's first chair in this discipline.
He discovered in 1919 an effect named after him, the Barkhausen effect
Barkhausen effect
The Barkhausen effect is a name given to the noise in the magnetic output of a ferromagnet when the magnetizing force applied to it is changed...
, which suggested that ferromagnetic materials contain regions of like-oriented atoms. Induced changes in the magnetic orientation of these domains affect the whole domain and not individual atoms. With suitable equipment, these changes of orientation (jumps) can be heard.
The Barkhausen stability criterion
Barkhausen stability criterion
The Barkhausen stability criterion is a mathematical condition to determine when a linear electronic circuit will oscillate. It was put forth in 1921 by German physicist Heinrich Georg Barkhausen...
states that an oscillator will oscillate when the total phase shift
Phase (waves)
Phase in waves is the fraction of a wave cycle which has elapsed relative to an arbitrary point.-Formula:The phase of an oscillation or wave refers to a sinusoidal function such as the following:...
from input to output back to input is an integral multiple of 360 degrees and the system gain is equal to 1.