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Julius Edgar Lilienfeld

1882 – 1963

Austro-Hungarian physicist

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About Julius Edgar Lilienfeld

Lived 1882 – 1963 (aged 81). Julius Edgar Lilienfeld was an Austrian and American physicist, inventor, university teacher and electrical engineer, known for Electrolytic capacitor and Field-effect transistor.

Julius Edgar Lilienfeld (April 18, 1882 – August 28, 1963) was an Austro-Hungarian, and later American (where he moved in 1921) electrical engineer and physicist who has been credited with the first patent on the field-effect transistor in 1925. He was never able to build a working practical semiconductor device based on his concept. Additionally, because he didn't publish articles in learned journals and since high-purity semiconductor materials were not available to him, his FET patent never achieved fame, causing confusion for later inventors.

Early life Lilienfeld was born to a Jewish family in Lemberg (present-day Lviv) in the Austrian part of the Austro-Hungarian Empire. Lilienfeld's father was the lawyer Sigmund Lilienfeld, his mother Sarah Jampoler Lilienfeld.

Education After graduating high school in 1899, His early passion was to clarify how this phenomenon changed as vacuum preparation techniques improved. More than any other scientist, he was responsible for the identification of field electron emission as a separate physical effect. (He called it "auto-electronic emission", and was interested in it as a possible electron source for miniaturised X-ray tubes, in medical applications.) Lilienfeld was responsible for the first reliable account in English of the experimental phenomenology of field electron emission, in 1922. The effect was explained by Fowler and Nordheim in 1928.

Lilienfeld moved to the United States in 1921 to pursue his patent claims, resigning his professorship at Leipzig to stay permanently in 1926. In 1928, he began working at Amrad in Malden, Massachusetts, later called Ergon Research Laboratories owned by Magnavox, which closed in 1935. for a FET-like transistor was granted January 28, 1930.) When Brattain, Bardeen, and their colleague chemist Robert Gibney tried to get patents on their earliest devices, most of their claims were rejected due to the Lilienfeld patents.

The optical radiation emitted when electrons strike a metal surface is named "Lilienfeld radiation" after he first discovered it close to X-ray tube anodes. Its origin is attributed to the excitation of plasmons in the metal surface.

The American Physical Society has named one of its major prizes after Lilienfeld.

Personal life Lilienfeld was a German-speaking Ashkenazi Jew who was a citizen of Austria-Hungary and later had dual citizenship in the United States and in Poland. He married an American, Beatrice Ginsburg, in New York City on May 2, 1926. They lived in Winchester, Massachusetts, where Lilienfeld was director of the Ergon Research Laboratories in Malden, becoming a United States citizen in 1934. After it closed in 1935, he and his wife built a house on St. Thomas in the U.S. Virgin Islands in hope of escaping an allergy associated with wheat fields, from which Lilienfeld had suffered for most of his life. Lilienfeld frequently traveled between St. Thomas and various mainland locations and continued to test new ideas and patent the resulting products.

Patents

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Important facts

Birth century
Known for
Electrolytic capacitor, Field-effect transistor
Education
Humboldt-Universität zu Berlin, Humboldt University of Berlin, Leipzig University
Employers
Leipzig University

Contemporaries

People whose lives overlapped Julius Edgar Lilienfeld's

Frequently asked questions

Who was Julius Edgar Lilienfeld?

Austro-Hungarian physicist

When was Julius Edgar Lilienfeld born?

Julius Edgar Lilienfeld was born on 18 April 1882 in Lviv.

When did Julius Edgar Lilienfeld die?

Julius Edgar Lilienfeld died on 28 August 1963 in Charlotte Amalie.

What was Julius Edgar Lilienfeld's occupation?

Julius Edgar Lilienfeld was a physicist, inventor, university teacher and electrical engineer.

What was Julius Edgar Lilienfeld known for?

Julius Edgar Lilienfeld was known for Electrolytic capacitor and Field-effect transistor.

What nationality was Julius Edgar Lilienfeld?

Julius Edgar Lilienfeld was Austrian and American.

Sources & further reading

· Wikipedia: Julius Edgar Lilienfeld

· Wikidata: Q697195

· DBpedia: Julius Edgar Lilienfeld

Cite this page

APA: Biography.guide. (2026). Julius Edgar Lilienfeld. https://biography.guide/julius-edgar-lilienfeld/

MLA: "Julius Edgar Lilienfeld." Biography.guide, https://biography.guide/julius-edgar-lilienfeld/.

Chicago: "Julius Edgar Lilienfeld." Biography.guide. https://biography.guide/julius-edgar-lilienfeld/.

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