Ticker symbol parks in the United States, uses "FUN" as its symbol. Harley-Davidson uses "HOG" for its Harley Owners Group. Yamana Gold uses "AUY", because on the periodic table of elements, "Au" is the symbol for gold. Sotheby's (the famous auction house) uses the symbol "BID". While most symbols come from the company's name, sometimes it happens the other way around. Tricon Global, owner of KFC, Pizza Hut and Taco Bell, adopted the symbol "YUM" to represent its corporate mission when the company was spun out of PepsiCo in 1997. In 2002, the company changed its name to match its symbol, adopting
Chemical potential function, Fermi energy, and Fermi level. For example, n-type silicon has a higher internal chemical potential of electrons than p-type silicon. In a p–n junction diode at equilibrium the chemical potential ("internal" chemical potential) varies from the p-type to the n-type side, while the total chemical potential (electrochemical potential, or, Fermi level) is constant throughout the diode. As described above, when describing chemical potential, one has to say "relative to what". In the case of electrons in semiconductors, internal chemical potential is often specified relative to some convenient point in the band structure, e.g., to the bottom of the conduction