Abstract: An object is to provide a light-emitting element capable of emitting light with a high luminance even at a low voltage, and having a long lifetime. The light-emitting element includes n EL layers between an anode and a cathode (n is a natural number of two or more), and also includes, between m-th EL layer from the anode and (m+1)-th EL layer (m is a natural number, 1?m?n?1), a first layer including a first donor material in contact with the m-th EL layer, a second layer including an electron-transport material and a second donor material in contact with the first layer, and a third layer including a hole-transport material and an acceptor material in contact with the second layer and the (m+1)-th EL layer.

Abstract: Light-emitting elements in which an increase of driving voltage can be suppressed are provided. Light-emitting devices whose power consumption is reduced by including such light-emitting elements are also provided. In a light-emitting element having an EL layer between an anode and a cathode, a first layer in which carriers can be produced is formed between the cathode and the EL layer and in contact with the cathode, a second layer which transfers electrons produced in the first layer is formed in contact with the first layer, and a third layer which injects the electrons received from the second layer into the EL layer is formed in contact with the second layer.

Abstract: A composite material including an organic compound and an inorganic compound and having a high carrier-transport property is provided. A composite material having a high carrier-injection property to an organic compound is provided. A composite material in which light absorption due to charge transfer interaction is unlikely to occur is provided. A light-emitting element having high emission efficiency is provided by including the composite material. A light-emitting element having a low drive voltage is provided. A light-emitting element having a long lifetime is provided. A composite material including a heterocyclic compound having a dibenzothiophene skeleton or a dibenzofuran skeleton and an inorganic compound exhibiting an electron-accepting property with respect to the heterocyclic compound is provided.

Abstract: An object is to provide a light-emitting element capable of emitting light with a high luminance even at a low voltage, and having a long lifetime. The light-emitting element includes n EL layers between an anode and a cathode (n is a natural number of two or more), and also includes, between m-th EL layer from the anode and (m+1)-th EL layer (m is a natural number, 1?m?n?1), a first layer including a first donor material in contact with the m-th EL layer, a second layer including an electron-transport material and a second donor material in contact with the first layer, and a third layer including a hole-transport material and an acceptor material in contact with the second layer and the (m+1)-th EL layer.

Abstract: An object is to provide a light-emitting element capable of emitting light with a high luminance even at a low voltage, and having a long lifetime. The light-emitting element includes n EL layers between an anode and a cathode (n is a natural number of two or more), and also includes, between m-th EL layer from the anode and (m+1)-th EL layer (m is a natural number, 1?m?n?1), a first layer including a first donor material in contact with the m-th EL layer, a second layer including an electron-transport material and a second donor material in contact with the first layer, and a third layer including a hole-transport material and an acceptor material in contact with the second layer and the (m+1)-th EL layer.

Abstract: An object is to provide a light-emitting element with high emission efficiency which includes a novel carbazole derivative that has a wide energy gap and can be used for a transport layer or a host material in a light-emitting element. A carbazole derivative in which the 4-position of dibenzothiophene or dibenzofuran is bonded to the 2- or 3-position of carbazole has been able to be provided by use of the carbazole derivative. Further, a light-emitting element having high emission efficiency has been able to be provided by use of the carbazole derivative.

Abstract: A composite material which includes an organic compound and an inorganic compound and has a high carrier-transport property is provided. A composite material having a good property of carrier injection into an organic compound is provided. A composite material in which light absorption due to charge-transfer interaction is unlikely to occur is provided. A composite material having a high visible-light-transmitting property is provided. A composite material including a hydrocarbon compound and an inorganic compound exhibiting an electron-accepting property with respect to the hydrocarbon compound is provided. The hydrocarbon compound has a substituent bonded to a naphthalene skeleton, a phenanthrene skeleton, or a triphenylene skeleton and has a molecular weight of 350 to 2000, and the substituent has one or more rings selected from a benzene ring, a naphthalene ring, a phenanthrene ring, and a triphenylene ring.

Abstract: Light-emitting elements in which an increase of driving voltage can be suppressed are provided. Light-emitting devices whose power consumption is reduced by including such light-emitting elements are also provided. In a light-emitting element having an EL layer between an anode and a cathode, a first layer in which carriers can be produced is formed between the cathode and the EL layer and in contact with the cathode, a second layer which transfers electrons produced in the first layer is formed in contact with the first layer, and a third layer which injects the electrons received from the second layer into the EL layer is formed in contact with the second layer.

Abstract: A novel substance with which an increase in life and emission efficiency of a light-emitting element can be achieved is provided. A carbazole compound having a structure represented by General Formula (G1) is provided. Note that a substituent which makes the HOMO level and the LUMO level of a compound in which a bond of the substituent is substituted with hydrogen deep and shallow, respectively is used as each of substituents in General Formula (G1) (R1, R2, Ar3, and ?3). Further, a subsistent which makes the band gap (Bg) and the T1 level of a compound in which a bond of the substituent is substituted with hydrogen wide and high is used as each of the substituents in General Formula (G1) (R1, R2, Ar3, and ?3).

Abstract: Light-emitting elements in which an increase of driving voltage can be suppressed are provided. Light-emitting devices whose power consumption is reduced by including such light-emitting elements are also provided. In a light-emitting element having an EL layer between an anode and a cathode, a first layer in which carriers can be produced is formed between the cathode and the EL layer and in contact with the cathode, a second layer which transfers electrons produced in the first layer is formed in contact with the first layer, and a third layer which injects the electrons received from the second layer into the EL layer is formed in contact with the second layer.

Abstract: A novel substance with which an increase in life and emission efficiency of a light-emitting element can be achieved is provided. A carbazole compound having a structure represented by General Formula (G1) is provided. Note that a substituent which makes the HOMO level and the LUMO level of a compound in which a bond of the substituent is substituted with hydrogen deep and shallow, respectively is used as each of substituents in General Formula (G1) (R1, R2, Ar3, and ?3). Further, a substituent which makes the band gap (Bg) and the T1 level of a compound in which a bond of the substituent is substituted with hydrogen wide and high is used as each of the substituents in General Formula (G1) (R1, R2, Ar3, and ?3).

Abstract: A novel substance with which an increase in life and emission efficiency of a light-emitting element can be achieved is provided. A carbazole compound having a structure represented by General Formula (G1) is provided. Note that a substituent which makes the HOMO level and the LUMO level of a compound in which a bond of the substituent is substituted with hydrogen deep and shallow, respectively is used as each of substituents in General Formula (G1) (R1, R2, Ar3, and ?3). Further, a subsistent which makes the band gap (Bg) and the T1 level of a compound in which a bond of the substituent is substituted with hydrogen wide and high is used as each of the substituents in General Formula (G1) (R1, R2, Ar3, and ?3).

Abstract: A composite material which includes an organic compound and an inorganic compound and has a high carrier-transport property is provided. A composite material having a good property of carrier injection into an organic compound is provided. A composite material in which light absorption due to charge-transfer interaction is unlikely to occur is provided. A composite material having a high visible-light-transmitting property is provided. A composite material including a hydrocarbon compound and an inorganic compound exhibiting an electron-accepting property with respect to the hydrocarbon compound is provided. The hydrocarbon compound has a substituent bonded to a naphthalene skeleton, a phenanthrene skeleton, or a triphenylene skeleton and has a molecular weight of 350 to 2000, and the substituent has one or more rings selected from a benzene ring, a naphthalene ring, a phenanthrene ring, and a triphenylene ring.

Abstract: A novel substance with which an increase in life and emission efficiency of a light-emitting element can be achieved is provided. A carbazole compound having a structure represented by General Formula (G1) is provided. Note that a substituent which makes the HOMO level and the LUMO level of a compound in which a bond of the substituent is substituted with hydrogen deep and shallow, respectively is used as each of substituents in General Formula (G1) (R1, R2, Ar3, and ?3). Further, a substituent which makes the band gap (Bg) and the T1 level of a compound in which a bond of the substituent is substituted with hydrogen wide and high is used as each of the substituents in General Formula (G1) (R1, R2, Ar3, and ?3).

Abstract: A composite material which includes an organic compound and an inorganic compound and has a high carrier-transport property is provided. A composite material having a good property of carrier injection into an organic compound is provided. A composite material in which light absorption due to charge-transfer interaction is unlikely to occur is provided. A composite material having a high visible-light-transmitting property is provided. A composite material including a hydrocarbon compound and an inorganic compound exhibiting an electron-accepting property with respect to the hydrocarbon compound is provided. The hydrocarbon compound has a substituent bonded to a naphthalene skeleton, a phenanthrene skeleton, or a triphenylene skeleton and has a molecular weight of 350 to 2000, and the substituent has one or more rings selected from a benzene ring, a naphthalene ring, a phenanthrene ring, and a triphenylene ring.

Abstract: An object is to provide a light-emitting element capable of emitting light with a high luminance even at a low voltage, and having a long lifetime. The light-emitting element includes n EL layers between an anode and a cathode (n is a natural number of two or more), and also includes, between m-th EL layer from the anode and (m+1)-th EL layer (m is a natural number, 1?m?n?1), a first layer including a first donor material in contact with the m-th EL layer, a second layer including an electron-transport material and a second donor material in contact with the first layer, and a third layer including a hole-transport material and an acceptor material in contact with the second layer and the (m+1)-th EL layer.

Abstract: An object is to provide a light-emitting element capable of emitting light with a high luminance even at a low voltage, and having a long lifetime. The light-emitting element includes n EL layers between an anode and a cathode (n is a natural number of two or more), and also includes, between m-th EL layer from the anode and (m+1)-th EL layer (m is a natural number, 1?m?n?1), a first layer including a first donor material in contact with the m-th EL layer, a second layer including an electron-transport material and a second donor material in contact with the first layer, and a third layer including a hole-transport material and an acceptor material in contact with the second layer and the (m+1)-th EL layer.

Abstract: Provided is a novel substance that can emit phosphorescence. Alternatively, provided is a novel substance with high emission efficiency. An organometallic complex in which a 4-arylpyrimidine derivative is a ligand and iridium is a central metal is provided. Specifically, an organometallic complex having a structure represented by a general formula (G1) is provided. In the general formula (G1), R1 represents a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms or a substituted or unsubstituted aryl group having 6 to 10 carbon atoms, R2 represents any of hydrogen, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, and a substituted or unsubstituted phenyl group, R3 represents hydrogen or a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, and Ar1 represents a substituted or unsubstituted arylene group having 6 to 10 carbon atoms.

Abstract: A composite material which includes an organic compound and an inorganic compound and has a high carrier-transport property is provided. A composite material having a good property of carrier injection into an organic compound is provided. A composite material in which light absorption due to charge-transfer interaction is unlikely to occur is provided. A composite material having a high visible-light-transmitting property is provided. A composite material including a hydrocarbon compound and an inorganic compound exhibiting an electron-accepting property with respect to the hydrocarbon compound is provided. The hydrocarbon compound has a substituent bonded to a naphthalene skeleton, a phenanthrene skeleton, or a triphenylene skeleton and has a molecular weight of 350 to 2000, and the substituent has one or more rings selected from a benzene ring, a naphthalene ring, a phenanthrene ring, and a triphenylene ring.

Abstract: A light-emitting element is provided, in which n (n is a natural number of two or more) EL layers are provided between an anode and a cathode. Between the m-th (m is a natural number, 1?m?n?1) EL layer and the (m+1)-th EL layer, a first layer containing any of an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth metal compound, and a rare earth metal compound, a second layer containing a substance having high electron-transport properties in contact with the first layer, and a charge-generation layer containing a substance having high hole-transport properties and an acceptor substance in contact with the second layer are provided in this order over the anode. The charge-generation layer does not have a peak of an absorption spectrum in a visible light region.