جان باردین (به انگلیسی: John Bardeen) مهندس و فیزیکدان آمریکایی بود که برندهٔ دو جایزه نوبل فیزیک و مدال افتخار انجمن مهندسان برق و الکترونیک IEEE شد. او از مخترعان ترانزیستور میباشد و تنها فیزیکدانی است که تاکنون دو بار موفق به دریافت جایزه نوبل فیزیک شدهاست. در سال ۱۹۹۰، نام او در میان ۱۰۰ آمریکایی تأثیرگذار قرن در مجله لایف قرار گرفت.
باردین در شهر مَدیسون در ایالت ویسکانسین آمریکا زاده شد. پدر او، چارلز باردین، نخستین رئیس دانشکده پزشکی دانشگاه ویسکانسین بود. باردین تحصیلات مقدماتیاش را در شهر زادگاهش، مدیسون، در ویسکانسین گذراند. او در ۱۵ سالگی از دبیرستان فارغالتحصیل شد و در همان سن تحصیلات دانشگاهی خود را در دانشگاه ویسکانسین شروع کرد. او بر خلاف پدرش که یک فرهنگی دانشگاهی بود، برای ادامه تحصیل رشته مهندسی را انتخاب کرد چون به ریاضیات علاقه فراوان داشت و به نظرش مهندسی آینده کاری خوبی هم داشت. وی تحصیلات دانشگاهی خود را در رشته مهندسی برق در مقاطع کارشناسی و کارشناسی ارشد از دانشگاه ویسکانسین-مدیسن به ترتیب در سالهای ۱۹۲۸ و ۱۹۲۹ میلادی به پایان رساند و در سال ۱۹۳۶ میلادی از دانشگاه پرینستون در رشته ریاضی فیزیک درجه دکترا گرفت. او دو سال بعد به دانشگاه مینهسوتا پیوست و از سال ۱۹۳۸ تا ۱۹۴۱ با درجه استادیاری فیزیک در آنجا تدریس کرد. در سال ۱۹۴۱، در دوران جنگ جهانی دوم، او تدریس در مینهسوتا را رها کرد و به عنوان فیزیکدان در آزمایشگاه نیروی دریایی مشغول شد. باردین در سال ۱۹۴۵ میلادی به آزمایشگاههای تلفن گراهام بل پیوست. در آنجا بود که با همکاری ویلیام شاکلی و والتر برتن به اختراع ترانزیستور توفیق یافت و به اشتراک این دو به دریافت جایزه نوبل فیزیک سال ۱۹۵۶ میلادی نایل آمد. باردین از سال ۱۹۵۱ به بعد با درجهٔ استادی فیزیک در دانشگاه ایلینوی مشغول به کار شد. در سال ۱۹۷۱، انجمن مهندسان برق و الکترونیک به پاس خدمات ارزنده جان باردین در درک رسانش الکتریکی جامدات، اختراع ترانزیستور و همچنین ارائه نظریه میکروسکوپی ابررسانایی، به او مدال افتخار خود را اهدا کرد. همچنین یک سال بعد در سال ۱۹۷۲، باردین به همراه لئون نیل کوپر و جان رابرت شریفر دومین جایزه نوبل فیزیک خود را برای ارائه نظریه بیسیاس در مورد ابررسانایی به دست آورد. او تنها فیزیکدانی است که دو بار موفق به دریافت جایزه نوبل فیزیک شدهاست. وی در سال ۱۹۹۱ در سن ۸۲ سالگی درگذشت.
دانشگاه ایلینوی در اِربانا-شَمپِین[ویرایش]
باردین در ۱۹۵۱ با ترک آزمایشگاههای بل به دانشکدههای مهندسی برق و فیزیک در دانشگاه ایلینوی در اربانا شمپین پیوست. در ایلینوی، وی دو برنامه تحقیقاتی مهم ایجاد کرد، یکی در دانشکده مهندسی برق و دیگری در دانشکده فیزیک. برنامه تحقیقاتی در دانشکده مهندسی برق، به هر دو جنبه تجربی و نظری دربارهٔ نیمههادیها و برنامه تحقیقاتی در گروه فیزیک، به جنبههای نظری سیستمهای کوانتومی ماکروسکوپی، به ویژه ابررسانایی و مایعات کوانتومی میپرداخت. وی از سال ۱۹۵۲ تا ۱۹۷۵ یک استاد فعال در ایلینوی بود و سپس در ۱۹۷۵ بازنشسته شد. پس از بازنشستگی، باردین تحقیقات خود را در طول دهه ۱۹۸۰ ادامه داد و مقالاتی را در مجلات علمی فیزیکال ریویو لترز و فیزیک امروز تا کمتر از یک سال قبل از درگذشتش منتشر کرد.
اولین دانشجوی دکترای او در دانشگاه ایلینوی، نیک هولونیاک (۱۹۵۴)، اولین ال ای دی (دیود نورافشان) را در ۱۹۶۲ اختراع کرد و همچنین موفق به دریافت دو جایزه ارزنده مدال افتخار و مدال ادیسون از انجمن مهندسان برق و الکترونیک شد.
دانشگاه ایلینوی به افتخار پروفسور جان باردین، محوطه چهارگوشهٔ مهندسی مشهور خود را چهارگوش باردین نامگذاری کردهاست.
John Bardeen (//; May 23, 1908 – January 30, 1991) was an American physicist and electrical engineer. He is the only person to be awarded the Nobel Prize in Physics twice: first in 1956 with William Shockley and Walter Brattain for the invention of the transistor; and again in 1972 with Leon N Cooper and John Robert Schrieffer for a fundamental theory of conventional superconductivity known as the BCS theory.
The transistor revolutionized the electronics industry, making possible the development of almost every modern electronic device, from telephones to computers, and ushering in the Information Age. Bardeen's developments in superconductivity—for which he was awarded his second Nobel Prize—are used in nuclear magnetic resonance spectroscopy (NMR) and medical magnetic resonance imaging (MRI).
Education and early life
Bardeen attended the University High School at Madison. He graduated from the school in 1923 at age 15. He could have graduated several years earlier, but this was postponed because he took courses at another high school and because of his mother's death. He entered the University of Wisconsin in 1923. While in college, he joined the Zeta Psi fraternity. He raised the needed membership fees partly by playing billiards. He was initiated as a member of Tau Beta Pi engineering honor society. He chose engineering because he did not want to be an academic like his father. He also felt that engineering had good job prospects.
Bardeen received his Bachelor of Science degree in electrical engineering in 1928 from the University of Wisconsin–Madison. He graduated in 1928 despite taking a year off to work in Chicago. He took all the graduate courses in physics and mathematics that had interested him, and he graduated in five years instead of the usual four. This allowed him time to complete his Master's thesis, which was supervised by Leo J. Peters. He received his Master of Science degree in electrical engineering in 1929 from Wisconsin.
Bardeen furthered his studies by staying on at Wisconsin, but he eventually went to work for Gulf Research Laboratories, the research arm of the Gulf Oil Corporation that was based in Pittsburgh. From 1930 to 1933, Bardeen worked there on the development of methods for the interpretation of magnetic and gravitational surveys. He worked as a geophysicist. After the work failed to keep his interest, he applied and was accepted to the graduate program in mathematics at Princeton University.
As a graduate student, Bardeen studied mathematics and physics. Under physicist Eugene Wigner, he ended up writing his thesis on a problem in solid-state physics. Before completing his thesis, he was offered a position as Junior Fellow of the Society of Fellows at Harvard University in 1935. He spent the next three years there, from 1935 to 1938, working with to-be Nobel laureates in physics John Hasbrouck van Vleck and Percy Williams Bridgman on problems in cohesion and electrical conduction in metals, and also did some work on level density of nuclei. He received his Ph.D. in mathematical physics from Princeton in 1936.
Career and research
World War II Service
From 1941 to 1944, Bardeen headed the group working on magnetic mines and torpedoes and mine and torpedo countermeasures at the Naval Ordnance Laboratory. During this period his wife Jane gave birth to a son (Bill, born in 1941) and a daughter (Betsy, born in 1944).
In October 1945, Bardeen began work at Bell Labs. He was a member of a solid-state physics group, led by William Shockley and chemist Stanley Morgan. Other personnel working in the group were Walter Brattain, physicist Gerald Pearson, chemist Robert Gibney, electronics expert Hilbert Moore and several technicians. He moved his family to Summit, New Jersey.
The assignment of the group was to seek a solid-state alternative to fragile glass vacuum tube amplifiers. Their first attempts were based on Shockley's ideas about using an external electrical field on a semiconductor to affect its conductivity. These experiments mysteriously failed every time in all sorts of configurations and materials. The group was at a standstill until Bardeen suggested a theory that invoked surface states that prevented the field from penetrating the semiconductor. The group changed its focus to study these surface states, and they met almost daily to discuss the work. The rapport of the group was excellent, and ideas were freely exchanged. By the winter of 1946 they had enough results that Bardeen submitted a paper on the surface states to Physical Review. Brattain started experiments to study the surface states through observations made while shining a bright light on the semiconductor's surface. This led to several more papers (one of them co-authored with Shockley), which estimated the density of the surface states to be more than enough to account for their failed experiments. The pace of the work picked up significantly when they started to surround point contacts between the semiconductor and the conducting wires with electrolytes. Moore built a circuit that allowed them to vary the frequency of the input signal easily and suggested that they use glycol borate (gu), a viscous chemical that didn't evaporate. Finally they began to get some evidence of power amplification when Pearson, acting on a suggestion by Shockley, put a voltage on a droplet of gu placed across a p–n junction.
The invention of the transistor
On December 23, 1947, Bardeen and Brattain were working without Shockley when they succeeded in creating a point-contact transistor that achieved amplification. By the next month, Bell Labs' patent attorneys started to work on the patent applications.
Bell Labs' attorneys soon discovered that Shockley's field effect principle had been anticipated and patented in 1930 by Julius Lilienfeld, who filed his MESFET-like patent in Canada on October 22, 1925.
Shockley publicly took the lion's share of the credit for the invention of transistor; this led to a deterioration of Bardeen's relationship with Shockley. Bell Labs management, however, consistently presented all three inventors as a team. Shockley eventually infuriated and alienated Bardeen and Brattain, and he essentially blocked the two from working on the junction transistor. Bardeen began pursuing a theory for superconductivity and left Bell Labs in 1951. Brattain refused to work with Shockley further and was assigned to another group. Neither Bardeen nor Brattain had much to do with the development of the transistor beyond the first year after its invention.
The "transistor" (a portmanteau of "transconductance" and "resistor") was 1/50 the size of the vacuum tubes it replaced in televisions and radios, used far less power, was far more reliable, and it allowed electrical devices to become more compact.
University of Illinois at Urbana–Champaign
By 1951, Bardeen was looking for a new job. Fred Seitz, a friend of Bardeen, convinced the University of Illinois at Urbana–Champaign to make Bardeen an offer of $10,000 a year. Bardeen accepted the offer and left Bell Labs. He joined the engineering and physics faculties at the University of Illinois at Urbana–Champaign in 1951. He was Professor of Electrical Engineering and of Physics at Illinois. His Ph.D. student Nick Holonyak (1954), invented the LED in 1962.
At Illinois, he established two major research programs, one in the Electrical Engineering Department and one in the Physics Department. The research program in the Electrical Engineering Department dealt with both experimental and theoretical aspects of semiconductors, and the research program in the Physics Department dealt with theoretical aspects of macroscopic quantum systems, particularly superconductivity and quantum liquids.
He was an active professor at Illinois from 1951 to 1975 and then became Professor Emeritus. In his later life, Bardeen remained active in academic research, during which time he focused on understanding the flow of electrons in charge density waves (CDWs) through metallic linear chain compounds. His proposals that CDW electron transport is a collective quantum phenomenon (see Macroscopic quantum phenomena) were initially greeted with skepticism. However, experiments reported in 2012 show oscillations in CDW current versus magnetic flux through tantalum trisulfide rings, similar to the behavior of superconducting quantum interference devices (see SQUID and Aharonov–Bohm effect), lending credence to the idea that collective CDW electron transport is fundamentally quantum in nature. (See quantum mechanics.) Bardeen continued his research throughout the 1980s, and published articles in Physical Review Letters and Physics Today less than a year before he died.
The Nobel Prize in Physics in 1956
In 1956, John Bardeen shared the Nobel Prize in Physics with William Shockley of Semiconductor Laboratory of Beckman Instruments and Walter Brattain of Bell Telephone Laboratories "for their researches on semiconductors and their discovery of the transistor effect".
At the Nobel Prize ceremony in Stockholm, Brattain and Shockley received their awards that night from King Gustaf VI Adolf. Bardeen brought only one of his three children to the Nobel Prize ceremony. King Gustav chided Bardeen because of this, and Bardeen assured the King that the next time he would bring all his children to the ceremony. He kept his promise.
In 1957, Bardeen, in collaboration with Leon Cooper and his doctoral student John Robert Schrieffer, proposed the standard theory of superconductivity known as the BCS theory (named for their initials).
The Nobel Prize in Physics in 1972
In 1972, Bardeen shared the Nobel Prize in Physics with Leon N Cooper of Brown University and John Robert Schrieffer of the University of Pennsylvania "for their jointly developed theory of superconductivity, usually called the BCS-theory". This was Bardeen's second Nobel Prize in Physics. He became the first person to win two Nobel Prizes in the same field. Only three others have ever received more than one Nobel Prize.
In addition to being awarded the Nobel prize twice, Bardeen has numerous other awards including:
Bardeen was also an important adviser to Xerox Corporation. Though quiet by nature, he took the uncharacteristic step of urging Xerox executives to keep their California research center, Xerox PARC, afloat when the parent company was suspicious that its research center would amount to little.
Bardeen married Jane Maxwell on July 18, 1938. While at Princeton, he met Jane during a visit to his old friends in Pittsburgh.
Bardeen was a scientist with a very unassuming personality. While he served as a professor for almost 40 years at the University of Illinois, he was best remembered by neighbors for hosting cookouts where he would prepare food for his friends, many of whom were unaware of his accomplishments at the university. He would always ask his guests if they liked the hamburger bun toasted (since he liked his that way). He enjoyed playing golf and going on picnics with his family. Lillian Hoddeson, a University of Illinois historian who wrote a book on Bardeen, said that because he "differed radically from the popular stereotype of 'genius' and was uninterested in appearing other than ordinary, the public and the media often overlooked him."
When Bardeen was asked about his beliefs during a 1988 interview, he responded: "I am not a religious person, and so do not think about it very much". However, he has also said: "I feel that science cannot provide an answer to the ultimate questions about the meaning and purpose of life." Bardeen did believe in a code of moral values and behaviour. John Bardeen's children were taken to church by his wife, who taught Sunday school and was a church elder. Despite this, he and his wife made it clear that they did not have faith in an afterlife and other religious ideas.
Bardeen died of heart disease at age 82 at Brigham and Women's Hospital in Boston, Massachusetts, on January 30, 1991. Although he lived in Champaign-Urbana, he had come to Boston for medical consultation. Bardeen and his wife Jane (1907–1997) are buried in Forest Hill Cemetery, Madison, Wisconsin. They were survived by three children, James, William and Elizabeth Bardeen Greytak, and six grandchildren.
Near the end of this decade, when they begin enumerating the names of the people who had the greatest impact on the 20th century, the name of John Bardeen, who died last week, has to be near, or perhaps even arguably at, the top of the list ... Mr. Bardeen shared two Nobel Prizes and has been awarded numerous other honors. But what greater honor can there be when each of us can look all around us and everywhere see the reminders of a man whose genius has made our lives longer, healthier and better.
—Chicago Tribune editorial, February 3, 1991
In honor of Professor Bardeen, the engineering quadrangle at the University of Illinois at Urbana-Champaign is named the Bardeen Quad.
Also in honor of Bardeen, Sony Corporation endowed a $3 million John Bardeen professorial chair at the University of Illinois at Urbana-Champaign, beginning in 1990. SONY Corporation owed much of its success to commercializing Bardeen's transistors in portable TVs and radios, and had worked with Illinois researchers. The current John Bardeen Professor is Nick Holonyak, Bardeen's doctoral student and protege.
At the time of Bardeen's death, then-University of Illinois chancellor Morton Weir said, "It is a rare person whose work changes the life of every American; John's did."
Bardeen was honored on a March 6, 2008, United States postage stamp as part of the "American Scientists" series designed by artist Victor Stabin. The $0.41 stamp was unveiled in a ceremony at the University of Illinois. His citation reads: "Theoretical physicist John Bardeen (1908–1991) shared the Nobel Prize in Physics twice — in 1956, as co-inventor of the transistor and in 1972, for the explanation of superconductivity. The transistor paved the way for all modern electronics, from computers to microchips. Diverse applications of superconductivity include infrared sensors and medical imaging systems." The other scientists on the "American Scientists" sheet include biochemist Gerty Cori, chemist Linus Pauling and astronomer Edwin Hubble.